From e0023883c6d2e6745a19e4b48e186ed156c1fca8 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 17:19:27 +0200 Subject: Adding upstream version 2.11.2. Signed-off-by: Daniel Baumann --- src/manconv_client.c | 218 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 218 insertions(+) create mode 100644 src/manconv_client.c (limited to 'src/manconv_client.c') diff --git a/src/manconv_client.c b/src/manconv_client.c new file mode 100644 index 0000000..7cdb1b8 --- /dev/null +++ b/src/manconv_client.c @@ -0,0 +1,218 @@ +/* + * 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 +#include +#include + +#include "gl_array_list.h" +#include "gl_xlist.h" +#include "xalloc.h" +#include "xvasprintf.h" + +#include "manconfig.h" + +#include "pipeline.h" + +#include "appendstr.h" +#include "glcontainers.h" +#include "sandbox.h" +#include "security.h" + +#include "decompress.h" +#include "manconv.h" +#include "manconv_client.h" +#include "utf8.h" + +extern man_sandbox *sandbox; + +struct manconv_codes { + gl_list_t from; + char *to; +}; + +static void manconv_stdin (void *data) +{ + struct manconv_codes *codes = data; + decompress *decomp; + + decomp = decompress_fdopen (dup (STDIN_FILENO)); + decompress_start (decomp); + if (manconv (decomp, codes->from, codes->to, NULL) != 0) + /* manconv already wrote an error message to stderr. Just + * exit non-zero. + */ + exit (FATAL); + decompress_wait (decomp); + decompress_free (decomp); +} + +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; + + gl_list_free (codes->from); + free (codes->to); + free (codes); +} + +void add_manconv (pipeline *p, + const char *source_encoding, const char *target_encoding) +{ + struct manconv_codes *codes; + char *name; + pipecmd *cmd; + + if (STREQ (source_encoding, target_encoding)) + return; + + codes = xmalloc (sizeof *codes); + /* informational only; no shell quoting concerns */ + name = xasprintf ("%s -f ", MANCONV); + codes->from = new_string_list (GL_ARRAY_LIST, true); + if (STREQ (source_encoding, "UTF-8")) { + gl_list_add_last (codes->from, xstrdup (source_encoding)); + name = appendstr (name, source_encoding, (void *) 0); + } else { + gl_list_add_last (codes->from, xstrdup ("UTF-8")); + gl_list_add_last (codes->from, xstrdup (source_encoding)); + name = appendstr (name, "UTF-8:", source_encoding, (void *) 0); + } + codes->to = xasprintf ("%s//IGNORE", target_encoding); + /* 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 ()) { + gl_list_t from = codes->from; + const char *from_code; + char *sources = NULL; + + cmd = pipecmd_new_args (MANCONV, "-f", (void *) 0); + GL_LIST_FOREACH (from, from_code) { + sources = appendstr (sources, from_code, (void *) 0); + if (gl_list_next_node (from, from_node)) + 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); +} + +/* Convert the result of in-process decompression to a target encoding. + * + * This converts the buffered result of decompression to a new buffer, then + * replaces the decompress object's buffer with the converted one for use by + * later stages of processing. + * + * Returns zero on success or non-zero on failure. + */ +int manconv_inprocess (decompress *d, + const char *source_encoding, + const char *target_encoding) +{ + gl_list_t from; + char *to; + struct manconv_outbuf outbuf; + int ret = 0; + + if (STREQ (source_encoding, target_encoding)) + return 0; + + from = new_string_list (GL_ARRAY_LIST, true); + if (STREQ (source_encoding, "UTF-8")) + gl_list_add_last (from, xstrdup (source_encoding)); + else { + if (STREQ (target_encoding, "UTF-8")) { + /* If the target encoding is UTF-8, then instead of + * starting with trial conversion from UTF-8 to + * UTF-8, we can start by simply performing UTF-8 + * validation, avoiding a copy. (The source + * encoding cannot be UTF-8 in this case, since we + * already checked that the source and target + * encodings are different.) + */ + if (utf8_validate_len (decompress_inprocess_buf (d), + decompress_inprocess_len (d))) + goto out; + } else + gl_list_add_last (from, xstrdup ("UTF-8")); + gl_list_add_last (from, xstrdup (source_encoding)); + } + to = xasprintf ("%s//IGNORE", target_encoding); + + outbuf.len = 0; + /* UTF-8 uses at most four bytes per Unicode code point. We assume + * that this conversion will be no worse than 1:4. + */ + outbuf.max = decompress_inprocess_len (d) * 4; + outbuf.buf = xmalloc (outbuf.max); + + if (manconv (d, from, to, &outbuf) == 0) + decompress_inprocess_replace (d, outbuf.buf, outbuf.len); + else { + /* manconv already wrote an error message to stderr. Just + * return non-zero. + */ + free (outbuf.buf); + ret = -1; + } + + free (to); +out: + gl_list_free (from); + return ret; +} -- cgit v1.2.3