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Diffstat (limited to 'src/journal/journald-native.c')
| -rw-r--r-- | src/journal/journald-native.c | 420 |
1 files changed, 420 insertions, 0 deletions
diff --git a/src/journal/journald-native.c b/src/journal/journald-native.c new file mode 100644 index 0000000000..ac3183ece3 --- /dev/null +++ b/src/journal/journald-native.c @@ -0,0 +1,420 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +/*** + 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 <http://www.gnu.org/licenses/>. +***/ + +#include <unistd.h> +#include <stddef.h> +#include <sys/epoll.h> + +#include "socket-util.h" +#include "path-util.h" +#include "journald-server.h" +#include "journald-native.h" +#include "journald-kmsg.h" +#include "journald-console.h" +#include "journald-syslog.h" + +#define ENTRY_SIZE_MAX (1024*1024*64) +#define DATA_SIZE_MAX (1024*1024*64) + +static bool valid_user_field(const char *p, size_t l) { + 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 (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; +} + +void server_process_native_message( + Server *s, + const void *buffer, size_t buffer_size, + struct ucred *ucred, + struct timeval *tv, + const char *label, size_t label_len) { + + struct iovec *iovec = NULL; + unsigned n = 0, m = 0, j, tn = (unsigned) -1; + const char *p; + size_t remaining; + int priority = LOG_INFO; + char *identifier = NULL, *message = NULL; + + 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 */ + server_dispatch_message(s, iovec, n, m, ucred, tv, label, label_len, NULL, priority); + n = 0; + priority = LOG_INFO; + + 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 */ + + if (n+N_IOVEC_META_FIELDS >= m) { + struct iovec *c; + unsigned u; + + u = MAX((n+N_IOVEC_META_FIELDS+1) * 2U, 4U); + c = realloc(iovec, u * sizeof(struct iovec)); + if (!c) { + log_oom(); + break; + } + + iovec = c; + m = u; + } + + q = memchr(p, '=', e - p); + if (q) { + if (valid_user_field(p, q - p)) { + 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; + n++; + + /* We need to determine the priority + * of this entry for the rate limiting + * logic */ + if (l == 10 && + memcmp(p, "PRIORITY=", 9) == 0 && + p[9] >= '0' && p[9] <= '9') + priority = (priority & LOG_FACMASK) | (p[9] - '0'); + + else if (l == 17 && + memcmp(p, "SYSLOG_FACILITY=", 16) == 0 && + p[16] >= '0' && p[16] <= '9') + priority = (priority & LOG_PRIMASK) | ((p[16] - '0') << 3); + + else if (l == 18 && + memcmp(p, "SYSLOG_FACILITY=", 16) == 0 && + 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 && + memcmp(p, "SYSLOG_IDENTIFIER=", 18) == 0) { + char *t; + + t = strndup(p + 18, l - 18); + if (t) { + free(identifier); + identifier = t; + } + } else if (l >= 8 && + memcmp(p, "MESSAGE=", 8) == 0) { + char *t; + + t = strndup(p + 8, l - 8); + if (t) { + free(message); + message = t; + } + } + } + + 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 too large, ignoring."); + 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)) { + iovec[n].iov_base = k; + iovec[n].iov_len = (e - p) + 1 + l; + 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"); + + 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); + } + + server_dispatch_message(s, iovec, n, m, ucred, tv, label, label_len, NULL, priority); + +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, + struct ucred *ucred, + struct timeval *tv, + const char *label, size_t label_len) { + + struct stat st; + _cleanup_free_ void *p = NULL; + ssize_t n; + int r; + + assert(s); + assert(fd >= 0); + + if (!ucred || ucred->uid != 0) { + _cleanup_free_ char *sl = NULL, *k = NULL; + const char *e; + + if (asprintf(&sl, "/proc/self/fd/%i", fd) < 0) { + log_oom(); + return; + } + + r = readlink_malloc(sl, &k); + if (r < 0) { + log_error("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_safe(e)) { + log_error("Received file in subdirectory of allowed directories. Refusing."); + return; + } + } + + /* Data is in the passed file, since it didn't fit in a + * datagram. 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 */ + + if (fstat(fd, &st) < 0) { + log_error("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; + } + + p = malloc(st.st_size); + if (!p) { + log_oom(); + return; + } + + n = pread(fd, p, st.st_size, 0); + if (n < 0) + log_error("Failed to read file, ignoring: %s", strerror(-n)); + else if (n > 0) + server_process_native_message(s, p, n, ucred, tv, label, label_len); +} + +int server_open_native_socket(Server*s) { + union sockaddr_union sa; + int one, r; + struct epoll_event ev; + + 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) { + log_error("socket() failed: %m"); + return -errno; + } + + zero(sa); + sa.un.sun_family = AF_UNIX; + strncpy(sa.un.sun_path, "/run/systemd/journal/socket", sizeof(sa.un.sun_path)); + + unlink(sa.un.sun_path); + + r = bind(s->native_fd, &sa.sa, offsetof(union sockaddr_union, un.sun_path) + strlen(sa.un.sun_path)); + if (r < 0) { + log_error("bind() failed: %m"); + return -errno; + } + + chmod(sa.un.sun_path, 0666); + } else + fd_nonblock(s->native_fd, 1); + + one = 1; + r = setsockopt(s->native_fd, SOL_SOCKET, SO_PASSCRED, &one, sizeof(one)); + if (r < 0) { + log_error("SO_PASSCRED failed: %m"); + return -errno; + } + +#ifdef HAVE_SELINUX + one = 1; + r = setsockopt(s->syslog_fd, SOL_SOCKET, SO_PASSSEC, &one, sizeof(one)); + if (r < 0) + log_warning("SO_PASSSEC failed: %m"); +#endif + + one = 1; + r = setsockopt(s->native_fd, SOL_SOCKET, SO_TIMESTAMP, &one, sizeof(one)); + if (r < 0) { + log_error("SO_TIMESTAMP failed: %m"); + return -errno; + } + + zero(ev); + ev.events = EPOLLIN; + ev.data.fd = s->native_fd; + if (epoll_ctl(s->epoll_fd, EPOLL_CTL_ADD, s->native_fd, &ev) < 0) { + log_error("Failed to add native server fd to epoll object: %m"); + return -errno; + } + + return 0; +} |