X-Git-Url: http://andersk.mit.edu/gitweb/openssh.git/blobdiff_plain/b0f6943a5dc83eaaaba15ebce897e162c1624033..caba7de7d39b58f9f4fa9f33ca04531e0358e266:/sftp-server.c diff --git a/sftp-server.c b/sftp-server.c index 3c254e33..d9549f5b 100644 --- a/sftp-server.c +++ b/sftp-server.c @@ -1,4 +1,4 @@ -/* $OpenBSD: sftp-server.c,v 1.64 2006/07/22 19:08:54 stevesk Exp $ */ +/* $OpenBSD: sftp-server.c,v 1.78 2008/02/27 20:21:15 djm Exp $ */ /* * Copyright (c) 2000-2004 Markus Friedl. All rights reserved. * @@ -14,22 +14,31 @@ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ + #include "includes.h" #include +#include #include +#ifdef HAVE_SYS_TIME_H +# include +#endif #include #include #include #include -#include +#include +#include +#include +#include #include +#include +#include +#include "xmalloc.h" #include "buffer.h" -#include "bufaux.h" #include "log.h" -#include "xmalloc.h" #include "misc.h" #include "uidswap.h" @@ -128,7 +137,7 @@ string_from_portable(int pflags) #define PAPPEND(str) { \ if (*ret != '\0') \ strlcat(ret, ",", sizeof(ret)); \ - strlcat(ret, str, sizeof(ret)); \ + strlcat(ret, str, sizeof(ret)); \ } if (pflags & SSH2_FXF_READ) @@ -160,6 +169,7 @@ struct Handle { int fd; char *name; u_int64_t bytes_read, bytes_write; + int next_unused; }; enum { @@ -168,40 +178,46 @@ enum { HANDLE_FILE }; -Handle handles[100]; +Handle *handles = NULL; +u_int num_handles = 0; +int first_unused_handle = -1; -static void -handle_init(void) +static void handle_unused(int i) { - u_int i; - - for (i = 0; i < sizeof(handles)/sizeof(Handle); i++) - handles[i].use = HANDLE_UNUSED; + handles[i].use = HANDLE_UNUSED; + handles[i].next_unused = first_unused_handle; + first_unused_handle = i; } static int handle_new(int use, const char *name, int fd, DIR *dirp) { - u_int i; + int i; - for (i = 0; i < sizeof(handles)/sizeof(Handle); i++) { - if (handles[i].use == HANDLE_UNUSED) { - handles[i].use = use; - handles[i].dirp = dirp; - handles[i].fd = fd; - handles[i].name = xstrdup(name); - handles[i].bytes_read = handles[i].bytes_write = 0; - return i; - } + if (first_unused_handle == -1) { + if (num_handles + 1 <= num_handles) + return -1; + num_handles++; + handles = xrealloc(handles, num_handles, sizeof(Handle)); + handle_unused(num_handles - 1); } - return -1; + + i = first_unused_handle; + first_unused_handle = handles[i].next_unused; + + handles[i].use = use; + handles[i].dirp = dirp; + handles[i].fd = fd; + handles[i].name = xstrdup(name); + handles[i].bytes_read = handles[i].bytes_write = 0; + + return i; } static int handle_is_ok(int i, int type) { - return i >= 0 && (u_int)i < sizeof(handles)/sizeof(Handle) && - handles[i].use == type; + return i >= 0 && (u_int)i < num_handles && handles[i].use == type; } static int @@ -291,12 +307,12 @@ handle_close(int handle) if (handle_is_ok(handle, HANDLE_FILE)) { ret = close(handles[handle].fd); - handles[handle].use = HANDLE_UNUSED; xfree(handles[handle].name); + handle_unused(handle); } else if (handle_is_ok(handle, HANDLE_DIR)) { ret = closedir(handles[handle].dirp); - handles[handle].use = HANDLE_UNUSED; xfree(handles[handle].name); + handle_unused(handle); } else { errno = ENOENT; } @@ -310,7 +326,8 @@ handle_log_close(int handle, char *emsg) logit("%s%sclose \"%s\" bytes read %llu written %llu", emsg == NULL ? "" : emsg, emsg == NULL ? "" : " ", handle_to_name(handle), - handle_bytes_read(handle), handle_bytes_write(handle)); + (unsigned long long)handle_bytes_read(handle), + (unsigned long long)handle_bytes_write(handle)); } else { logit("%s%sclosedir \"%s\"", emsg == NULL ? "" : emsg, emsg == NULL ? "" : " ", @@ -323,7 +340,7 @@ handle_log_exit(void) { u_int i; - for (i = 0; i < sizeof(handles)/sizeof(Handle); i++) + for (i = 0; i < num_handles; i++) if (handles[i].use != HANDLE_UNUSED) handle_log_close(i, "forced"); } @@ -470,6 +487,9 @@ process_init(void) buffer_init(&msg); buffer_put_char(&msg, SSH2_FXP_VERSION); buffer_put_int(&msg, SSH2_FILEXFER_VERSION); + /* POSIX rename extension */ + buffer_put_cstring(&msg, "posix-rename@openssh.com"); + buffer_put_cstring(&msg, "1"); /* version */ send_msg(&msg); buffer_free(&msg); } @@ -654,7 +674,7 @@ process_fstat(void) debug("request %u: fstat \"%s\" (handle %u)", id, handle_to_name(handle), handle); fd = handle_to_fd(handle); - if (fd >= 0) { + if (fd >= 0) { ret = fstat(fd, &st); if (ret < 0) { status = errno_to_portable(errno); @@ -693,7 +713,8 @@ process_setstat(void) a = get_attrib(); debug("request %u: setstat name \"%s\"", id, name); if (a->flags & SSH2_FILEXFER_ATTR_SIZE) { - logit("set \"%s\" size %llu", name, a->size); + logit("set \"%s\" size %llu", + name, (unsigned long long)a->size); ret = truncate(name, a->size); if (ret == -1) status = errno_to_portable(errno); @@ -745,7 +766,8 @@ process_fsetstat(void) char *name = handle_to_name(handle); if (a->flags & SSH2_FILEXFER_ATTR_SIZE) { - logit("set \"%s\" size %llu", name, a->size); + logit("set \"%s\" size %llu", + name, (unsigned long long)a->size); ret = ftruncate(fd, a->size); if (ret == -1) status = errno_to_portable(errno); @@ -1060,6 +1082,23 @@ process_symlink(void) xfree(newpath); } +static void +process_extended_posix_rename(u_int32_t id) +{ + char *oldpath, *newpath; + + oldpath = get_string(NULL); + newpath = get_string(NULL); + debug3("request %u: posix-rename", id); + logit("posix-rename old \"%s\" new \"%s\"", oldpath, newpath); + if (rename(oldpath, newpath) == -1) + send_status(id, errno_to_portable(errno)); + else + send_status(id, SSH2_FX_OK); + xfree(oldpath); + xfree(newpath); +} + static void process_extended(void) { @@ -1068,7 +1107,10 @@ process_extended(void) id = get_int(); request = get_string(NULL); - send_status(id, SSH2_FX_OP_UNSUPPORTED); /* MUST */ + if (strcmp(request, "posix-rename@openssh.com") == 0) + process_extended_posix_rename(id); + else + send_status(id, SSH2_FX_OP_UNSUPPORTED); /* MUST */ xfree(request); } @@ -1091,7 +1133,7 @@ process(void) if (msg_len > SFTP_MAX_MSG_LENGTH) { error("bad message from %s local user %s", client_addr, pw->pw_name); - cleanup_exit(11); + sftp_server_cleanup_exit(11); } if (buf_len < msg_len + 4) return; @@ -1164,18 +1206,22 @@ process(void) break; } /* discard the remaining bytes from the current packet */ - if (buf_len < buffer_len(&iqueue)) - fatal("iqueue grew unexpectedly"); + if (buf_len < buffer_len(&iqueue)) { + error("iqueue grew unexpectedly"); + sftp_server_cleanup_exit(255); + } consumed = buf_len - buffer_len(&iqueue); - if (msg_len < consumed) - fatal("msg_len %d < consumed %d", msg_len, consumed); + if (msg_len < consumed) { + error("msg_len %d < consumed %d", msg_len, consumed); + sftp_server_cleanup_exit(255); + } if (msg_len > consumed) buffer_consume(&iqueue, msg_len - consumed); } /* Cleanup handler that logs active handles upon normal exit */ void -cleanup_exit(int i) +sftp_server_cleanup_exit(int i) { if (pw != NULL && client_addr != NULL) { handle_log_exit(); @@ -1186,7 +1232,7 @@ cleanup_exit(int i) } static void -usage(void) +sftp_server_usage(void) { extern char *__progname; @@ -1196,20 +1242,17 @@ usage(void) } int -main(int argc, char **argv) +sftp_server_main(int argc, char **argv, struct passwd *user_pw) { fd_set *rset, *wset; int in, out, max, ch, skipargs = 0, log_stderr = 0; ssize_t len, olen, set_size; SyslogFacility log_facility = SYSLOG_FACILITY_AUTH; - char *cp; + char *cp, buf[4*4096]; extern char *optarg; extern char *__progname; - /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ - sanitise_stdfd(); - __progname = ssh_get_progname(argv[0]); log_init(__progname, log_level, log_facility, log_stderr); @@ -1218,7 +1261,7 @@ main(int argc, char **argv) case 'c': /* * Ignore all arguments if we are invoked as a - * shell using "sftp-server -c command" + * shell using "sftp-server -c command" */ skipargs = 1; break; @@ -1232,12 +1275,12 @@ main(int argc, char **argv) break; case 'f': log_facility = log_facility_number(optarg); - if (log_level == SYSLOG_FACILITY_NOT_SET) + if (log_facility == SYSLOG_FACILITY_NOT_SET) error("Invalid log facility \"%s\"", optarg); break; case 'h': default: - usage(); + sftp_server_usage(); } } @@ -1245,22 +1288,20 @@ main(int argc, char **argv) if ((cp = getenv("SSH_CONNECTION")) != NULL) { client_addr = xstrdup(cp); - if ((cp = strchr(client_addr, ' ')) == NULL) - fatal("Malformed SSH_CONNECTION variable: \"%s\"", + if ((cp = strchr(client_addr, ' ')) == NULL) { + error("Malformed SSH_CONNECTION variable: \"%s\"", getenv("SSH_CONNECTION")); + sftp_server_cleanup_exit(255); + } *cp = '\0'; } else client_addr = xstrdup("UNKNOWN"); - if ((pw = getpwuid(getuid())) == NULL) - fatal("No user found for uid %lu", (u_long)getuid()); - pw = pwcopy(pw); + pw = pwcopy(user_pw); logit("session opened for local user %s from [%s]", pw->pw_name, client_addr); - handle_init(); - in = dup(STDIN_FILENO); out = dup(STDOUT_FILENO); @@ -1286,7 +1327,15 @@ main(int argc, char **argv) memset(rset, 0, set_size); memset(wset, 0, set_size); - FD_SET(in, rset); + /* + * Ensure that we can read a full buffer and handle + * the worst-case length packet it can generate, + * otherwise apply backpressure by stopping reads. + */ + if (buffer_check_alloc(&iqueue, sizeof(buf)) && + buffer_check_alloc(&oqueue, SFTP_MAX_MSG_LENGTH)) + FD_SET(in, rset); + olen = buffer_len(&oqueue); if (olen > 0) FD_SET(out, wset); @@ -1295,19 +1344,18 @@ main(int argc, char **argv) if (errno == EINTR) continue; error("select: %s", strerror(errno)); - cleanup_exit(2); + sftp_server_cleanup_exit(2); } /* copy stdin to iqueue */ if (FD_ISSET(in, rset)) { - char buf[4*4096]; len = read(in, buf, sizeof buf); if (len == 0) { debug("read eof"); - cleanup_exit(0); + sftp_server_cleanup_exit(0); } else if (len < 0) { error("read: %s", strerror(errno)); - cleanup_exit(1); + sftp_server_cleanup_exit(1); } else { buffer_append(&iqueue, buf, len); } @@ -1317,12 +1365,18 @@ main(int argc, char **argv) len = write(out, buffer_ptr(&oqueue), olen); if (len < 0) { error("write: %s", strerror(errno)); - cleanup_exit(1); + sftp_server_cleanup_exit(1); } else { buffer_consume(&oqueue, len); } } - /* process requests from client */ - process(); + + /* + * Process requests from client if we can fit the results + * into the output buffer, otherwise stop processing input + * and let the output queue drain. + */ + if (buffer_check_alloc(&oqueue, SFTP_MAX_MSG_LENGTH)) + process(); } }