diff options
Diffstat (limited to 'src/manconv_client.c')
| -rw-r--r-- | src/manconv_client.c | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/src/manconv_client.c b/src/manconv_client.c new file mode 100644 index 0000000..c150e01 --- /dev/null +++ b/src/manconv_client.c @@ -0,0 +1,147 @@ +/* + * manconv_client.c: use manconv in a pipeline + * + * Copyright (C) 2007, 2008, 2010 Colin Watson. + * + * This file is part of man-db. + * + * man-db is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * man-db 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with man-db; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#ifdef HAVE_CONFIG_H +# include "config.h" +#endif /* HAVE_CONFIG_H */ + +#include <string.h> +#include <stdlib.h> +#include <unistd.h> + +#include "idpriv.h" +#include "xvasprintf.h" + +#include "manconfig.h" + +#include "pipeline.h" +#include "decompress.h" +#include "sandbox.h" +#include "security.h" + +#include "manconv.h" +#include "manconv_client.h" + +extern man_sandbox *sandbox; + +struct manconv_codes { + char **from; + char *to; +}; + +static void manconv_stdin (void *data) +{ + struct manconv_codes *codes = data; + pipeline *p; + + p = decompress_fdopen (dup (STDIN_FILENO)); + pipeline_start (p); + manconv (p, codes->from, codes->to); + pipeline_wait (p); + pipeline_free (p); +} + +static void manconv_pre_exec (void *data) +{ + /* We must drop privileges before loading the sandbox, since our + * seccomp filter doesn't allow setresuid and friends. + */ + drop_privs (NULL); + sandbox_load (data); +} + +static void free_manconv_codes (void *data) +{ + struct manconv_codes *codes = data; + char **try_from; + + for (try_from = codes->from; *try_from; ++try_from) + free (*try_from); + free (codes->from); + free (codes->to); + free (codes); +} + +void add_manconv (pipeline *p, const char *source, const char *target) +{ + struct manconv_codes *codes; + char *name; + pipecmd *cmd; + + if (STREQ (source, "UTF-8") && STREQ (target, "UTF-8")) + return; + + codes = xmalloc (sizeof *codes); + /* informational only; no shell quoting concerns */ + name = xasprintf ("%s -f ", MANCONV); + if (STREQ (source, "UTF-8")) { + codes->from = XNMALLOC (2, char *); + codes->from[0] = xstrdup (source); + codes->from[1] = NULL; + name = appendstr (name, source, (void *) 0); + } else { + codes->from = XNMALLOC (3, char *); + codes->from[0] = xstrdup ("UTF-8"); + codes->from[1] = xstrdup (source); + codes->from[2] = NULL; + name = appendstr (name, "UTF-8:", source, (void *) 0); + } + codes->to = xasprintf ("%s//IGNORE", target); + /* informational only; no shell quoting concerns */ + name = appendstr (name, " -t ", codes->to, (void *) 0); + if (quiet >= 2) + name = appendstr (name, " -q", (void *) 0); + + /* iconv_open may not work correctly in setuid processes; in GNU + * libc, gconv modules may be linked against other gconv modules and + * rely on RPATH $ORIGIN to load those modules from the correct + * path, but $ORIGIN is disabled in setuid processes. It is + * impossible to reset libc's idea of setuidness without creating a + * whole new process image. Therefore, if the calling process is + * setuid, we must drop privileges and execute manconv. + */ + if (running_setuid ()) { + char **from_code; + char *sources = NULL; + + cmd = pipecmd_new_args (MANCONV, "-f", (void *) 0); + for (from_code = codes->from; *from_code; ++from_code) { + sources = appendstr (sources, *from_code, (void *) 0); + if (*(from_code + 1)) + sources = appendstr (sources, ":", (void *) 0); + } + pipecmd_arg (cmd, sources); + free (sources); + pipecmd_args (cmd, "-t", codes->to, (void *) 0); + if (quiet >= 2) + pipecmd_arg (cmd, "-q"); + pipecmd_pre_exec (cmd, manconv_pre_exec, sandbox_free, + sandbox); + free_manconv_codes (codes); + } else { + cmd = pipecmd_new_function (name, &manconv_stdin, + &free_manconv_codes, codes); + pipecmd_pre_exec (cmd, sandbox_load, sandbox_free, sandbox); + } + free (name); + pipeline_command (p, cmd); +} |