From 8231d17032fdd535e58c5aead8eae3f6cbc048b5 Mon Sep 17 00:00:00 2001 From: Luke Shumaker Date: Thu, 9 Jun 2016 03:13:06 -0400 Subject: ./move.sh --- src/grp-journal/libjournal-core/journald-native.c | 501 ++++++++++++++++++++++ 1 file changed, 501 insertions(+) create mode 100644 src/grp-journal/libjournal-core/journald-native.c (limited to 'src/grp-journal/libjournal-core/journald-native.c') diff --git a/src/grp-journal/libjournal-core/journald-native.c b/src/grp-journal/libjournal-core/journald-native.c new file mode 100644 index 0000000000..0a1ce205c2 --- /dev/null +++ b/src/grp-journal/libjournal-core/journald-native.c @@ -0,0 +1,501 @@ +/*** + This file is part of systemd. + + Copyright 2011 Lennart Poettering + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 2.1 of the License, or + (at your option) any later version. + + systemd is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with systemd; If not, see . +***/ + +#include +#include +#include +#include +#include + +#include "alloc-util.h" +#include "fd-util.h" +#include "fs-util.h" +#include "io-util.h" +#include "journald-console.h" +#include "journald-kmsg.h" +#include "journald-native.h" +#include "journald-server.h" +#include "journald-syslog.h" +#include "journald-wall.h" +#include "memfd-util.h" +#include "parse-util.h" +#include "path-util.h" +#include "selinux-util.h" +#include "socket-util.h" +#include "string-util.h" + +bool valid_user_field(const char *p, size_t l, bool allow_protected) { + const char *a; + + /* We kinda enforce POSIX syntax recommendations for + environment variables here, but make a couple of additional + requirements. + + http://pubs.opengroup.org/onlinepubs/000095399/basedefs/xbd_chap08.html */ + + /* No empty field names */ + if (l <= 0) + return false; + + /* Don't allow names longer than 64 chars */ + if (l > 64) + return false; + + /* Variables starting with an underscore are protected */ + if (!allow_protected && p[0] == '_') + return false; + + /* Don't allow digits as first character */ + if (p[0] >= '0' && p[0] <= '9') + return false; + + /* Only allow A-Z0-9 and '_' */ + for (a = p; a < p + l; a++) + if ((*a < 'A' || *a > 'Z') && + (*a < '0' || *a > '9') && + *a != '_') + return false; + + return true; +} + +static bool allow_object_pid(const struct ucred *ucred) { + return ucred && ucred->uid == 0; +} + +void server_process_native_message( + Server *s, + const void *buffer, size_t buffer_size, + const struct ucred *ucred, + const struct timeval *tv, + const char *label, size_t label_len) { + + struct iovec *iovec = NULL; + unsigned n = 0, j, tn = (unsigned) -1; + const char *p; + size_t remaining, m = 0, entry_size = 0; + int priority = LOG_INFO; + char *identifier = NULL, *message = NULL; + pid_t object_pid = 0; + + assert(s); + assert(buffer || buffer_size == 0); + + p = buffer; + remaining = buffer_size; + + while (remaining > 0) { + const char *e, *q; + + e = memchr(p, '\n', remaining); + + if (!e) { + /* Trailing noise, let's ignore it, and flush what we collected */ + log_debug("Received message with trailing noise, ignoring."); + break; + } + + if (e == p) { + /* Entry separator */ + + if (entry_size + n + 1 > ENTRY_SIZE_MAX) { /* data + separators + trailer */ + log_debug("Entry is too big with %u properties and %zu bytes, ignoring.", n, entry_size); + continue; + } + + server_dispatch_message(s, iovec, n, m, ucred, tv, label, label_len, NULL, priority, object_pid); + n = 0; + priority = LOG_INFO; + entry_size = 0; + + p++; + remaining--; + continue; + } + + if (*p == '.' || *p == '#') { + /* Ignore control commands for now, and + * comments too. */ + remaining -= (e - p) + 1; + p = e + 1; + continue; + } + + /* A property follows */ + + /* n existing properties, 1 new, +1 for _TRANSPORT */ + if (!GREEDY_REALLOC(iovec, m, n + 2 + N_IOVEC_META_FIELDS + N_IOVEC_OBJECT_FIELDS)) { + log_oom(); + break; + } + + q = memchr(p, '=', e - p); + if (q) { + if (valid_user_field(p, q - p, false)) { + size_t l; + + l = e - p; + + /* If the field name starts with an + * underscore, skip the variable, + * since that indidates a trusted + * field */ + iovec[n].iov_base = (char*) p; + iovec[n].iov_len = l; + entry_size += iovec[n].iov_len; + n++; + + /* We need to determine the priority + * of this entry for the rate limiting + * logic */ + if (l == 10 && + startswith(p, "PRIORITY=") && + p[9] >= '0' && p[9] <= '9') + priority = (priority & LOG_FACMASK) | (p[9] - '0'); + + else if (l == 17 && + startswith(p, "SYSLOG_FACILITY=") && + p[16] >= '0' && p[16] <= '9') + priority = (priority & LOG_PRIMASK) | ((p[16] - '0') << 3); + + else if (l == 18 && + startswith(p, "SYSLOG_FACILITY=") && + p[16] >= '0' && p[16] <= '9' && + p[17] >= '0' && p[17] <= '9') + priority = (priority & LOG_PRIMASK) | (((p[16] - '0')*10 + (p[17] - '0')) << 3); + + else if (l >= 19 && + startswith(p, "SYSLOG_IDENTIFIER=")) { + char *t; + + t = strndup(p + 18, l - 18); + if (t) { + free(identifier); + identifier = t; + } + + } else if (l >= 8 && + startswith(p, "MESSAGE=")) { + char *t; + + t = strndup(p + 8, l - 8); + if (t) { + free(message); + message = t; + } + + } else if (l > strlen("OBJECT_PID=") && + l < strlen("OBJECT_PID=") + DECIMAL_STR_MAX(pid_t) && + startswith(p, "OBJECT_PID=") && + allow_object_pid(ucred)) { + char buf[DECIMAL_STR_MAX(pid_t)]; + memcpy(buf, p + strlen("OBJECT_PID="), l - strlen("OBJECT_PID=")); + buf[l-strlen("OBJECT_PID=")] = '\0'; + + /* ignore error */ + parse_pid(buf, &object_pid); + } + } + + remaining -= (e - p) + 1; + p = e + 1; + continue; + } else { + le64_t l_le; + uint64_t l; + char *k; + + if (remaining < e - p + 1 + sizeof(uint64_t) + 1) { + log_debug("Failed to parse message, ignoring."); + break; + } + + memcpy(&l_le, e + 1, sizeof(uint64_t)); + l = le64toh(l_le); + + if (l > DATA_SIZE_MAX) { + log_debug("Received binary data block of %"PRIu64" bytes is too large, ignoring.", l); + break; + } + + if ((uint64_t) remaining < e - p + 1 + sizeof(uint64_t) + l + 1 || + e[1+sizeof(uint64_t)+l] != '\n') { + log_debug("Failed to parse message, ignoring."); + break; + } + + k = malloc((e - p) + 1 + l); + if (!k) { + log_oom(); + break; + } + + memcpy(k, p, e - p); + k[e - p] = '='; + memcpy(k + (e - p) + 1, e + 1 + sizeof(uint64_t), l); + + if (valid_user_field(p, e - p, false)) { + iovec[n].iov_base = k; + iovec[n].iov_len = (e - p) + 1 + l; + entry_size += iovec[n].iov_len; + n++; + } else + free(k); + + remaining -= (e - p) + 1 + sizeof(uint64_t) + l + 1; + p = e + 1 + sizeof(uint64_t) + l + 1; + } + } + + if (n <= 0) + goto finish; + + tn = n++; + IOVEC_SET_STRING(iovec[tn], "_TRANSPORT=journal"); + entry_size += strlen("_TRANSPORT=journal"); + + if (entry_size + n + 1 > ENTRY_SIZE_MAX) { /* data + separators + trailer */ + log_debug("Entry is too big with %u properties and %zu bytes, ignoring.", + n, entry_size); + goto finish; + } + + if (message) { + if (s->forward_to_syslog) + server_forward_syslog(s, priority, identifier, message, ucred, tv); + + if (s->forward_to_kmsg) + server_forward_kmsg(s, priority, identifier, message, ucred); + + if (s->forward_to_console) + server_forward_console(s, priority, identifier, message, ucred); + + if (s->forward_to_wall) + server_forward_wall(s, priority, identifier, message, ucred); + } + + server_dispatch_message(s, iovec, n, m, ucred, tv, label, label_len, NULL, priority, object_pid); + +finish: + for (j = 0; j < n; j++) { + if (j == tn) + continue; + + if (iovec[j].iov_base < buffer || + (const uint8_t*) iovec[j].iov_base >= (const uint8_t*) buffer + buffer_size) + free(iovec[j].iov_base); + } + + free(iovec); + free(identifier); + free(message); +} + +void server_process_native_file( + Server *s, + int fd, + const struct ucred *ucred, + const struct timeval *tv, + const char *label, size_t label_len) { + + struct stat st; + bool sealed; + int r; + + /* Data is in the passed fd, since it didn't fit in a + * datagram. */ + + assert(s); + assert(fd >= 0); + + /* If it's a memfd, check if it is sealed. If so, we can just + * use map it and use it, and do not need to copy the data + * out. */ + sealed = memfd_get_sealed(fd) > 0; + + if (!sealed && (!ucred || ucred->uid != 0)) { + _cleanup_free_ char *sl = NULL, *k = NULL; + const char *e; + + /* If this is not a sealed memfd, and the peer is unknown or + * unprivileged, then verify the path. */ + + if (asprintf(&sl, "/proc/self/fd/%i", fd) < 0) { + log_oom(); + return; + } + + r = readlink_malloc(sl, &k); + if (r < 0) { + log_error_errno(r, "readlink(%s) failed: %m", sl); + return; + } + + e = path_startswith(k, "/dev/shm/"); + if (!e) + e = path_startswith(k, "/tmp/"); + if (!e) + e = path_startswith(k, "/var/tmp/"); + if (!e) { + log_error("Received file outside of allowed directories. Refusing."); + return; + } + + if (!filename_is_valid(e)) { + log_error("Received file in subdirectory of allowed directories. Refusing."); + return; + } + } + + if (fstat(fd, &st) < 0) { + log_error_errno(errno, "Failed to stat passed file, ignoring: %m"); + return; + } + + if (!S_ISREG(st.st_mode)) { + log_error("File passed is not regular. Ignoring."); + return; + } + + if (st.st_size <= 0) + return; + + if (st.st_size > ENTRY_SIZE_MAX) { + log_error("File passed too large. Ignoring."); + return; + } + + if (sealed) { + void *p; + size_t ps; + + /* The file is sealed, we can just map it and use it. */ + + ps = PAGE_ALIGN(st.st_size); + p = mmap(NULL, ps, PROT_READ, MAP_PRIVATE, fd, 0); + if (p == MAP_FAILED) { + log_error_errno(errno, "Failed to map memfd, ignoring: %m"); + return; + } + + server_process_native_message(s, p, st.st_size, ucred, tv, label, label_len); + assert_se(munmap(p, ps) >= 0); + } else { + _cleanup_free_ void *p = NULL; + struct statvfs vfs; + ssize_t n; + + if (fstatvfs(fd, &vfs) < 0) { + log_error_errno(errno, "Failed to stat file system of passed file, ignoring: %m"); + return; + } + + /* Refuse operating on file systems that have + * mandatory locking enabled, see: + * + * https://github.com/systemd/systemd/issues/1822 + */ + if (vfs.f_flag & ST_MANDLOCK) { + log_error("Received file descriptor from file system with mandatory locking enable, refusing."); + return; + } + + /* Make the fd non-blocking. On regular files this has + * the effect of bypassing mandatory locking. Of + * course, this should normally not be necessary given + * the check above, but let's better be safe than + * sorry, after all NFS is pretty confusing regarding + * file system flags, and we better don't trust it, + * and so is SMB. */ + r = fd_nonblock(fd, true); + if (r < 0) { + log_error_errno(r, "Failed to make fd non-blocking, ignoring: %m"); + return; + } + + /* The file is not sealed, we can't map the file here, since + * clients might then truncate it and trigger a SIGBUS for + * us. So let's stupidly read it */ + + p = malloc(st.st_size); + if (!p) { + log_oom(); + return; + } + + n = pread(fd, p, st.st_size, 0); + if (n < 0) + log_error_errno(errno, "Failed to read file, ignoring: %m"); + else if (n > 0) + server_process_native_message(s, p, n, ucred, tv, label, label_len); + } +} + +int server_open_native_socket(Server*s) { + + static const union sockaddr_union sa = { + .un.sun_family = AF_UNIX, + .un.sun_path = "/run/systemd/journal/socket", + }; + static const int one = 1; + int r; + + assert(s); + + if (s->native_fd < 0) { + s->native_fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0); + if (s->native_fd < 0) + return log_error_errno(errno, "socket() failed: %m"); + + (void) unlink(sa.un.sun_path); + + r = bind(s->native_fd, &sa.sa, SOCKADDR_UN_LEN(sa.un)); + if (r < 0) + return log_error_errno(errno, "bind(%s) failed: %m", sa.un.sun_path); + + (void) chmod(sa.un.sun_path, 0666); + } else + fd_nonblock(s->native_fd, 1); + + r = setsockopt(s->native_fd, SOL_SOCKET, SO_PASSCRED, &one, sizeof(one)); + if (r < 0) + return log_error_errno(errno, "SO_PASSCRED failed: %m"); + +#ifdef HAVE_SELINUX + if (mac_selinux_have()) { + r = setsockopt(s->native_fd, SOL_SOCKET, SO_PASSSEC, &one, sizeof(one)); + if (r < 0) + log_warning_errno(errno, "SO_PASSSEC failed: %m"); + } +#endif + + r = setsockopt(s->native_fd, SOL_SOCKET, SO_TIMESTAMP, &one, sizeof(one)); + if (r < 0) + return log_error_errno(errno, "SO_TIMESTAMP failed: %m"); + + r = sd_event_add_io(s->event, &s->native_event_source, s->native_fd, EPOLLIN, server_process_datagram, s); + if (r < 0) + return log_error_errno(r, "Failed to add native server fd to event loop: %m"); + + r = sd_event_source_set_priority(s->native_event_source, SD_EVENT_PRIORITY_NORMAL+5); + if (r < 0) + return log_error_errno(r, "Failed to adjust native event source priority: %m"); + + return 0; +} -- cgit v1.2.3-54-g00ecf