diff options
Diffstat (limited to 'lib/libcapsicum/libcapsicum_grp.c')
| -rw-r--r-- | lib/libcapsicum/libcapsicum_grp.c | 426 |
1 files changed, 426 insertions, 0 deletions
diff --git a/lib/libcapsicum/libcapsicum_grp.c b/lib/libcapsicum/libcapsicum_grp.c new file mode 100644 index 000000000000..c679ce9afbd8 --- /dev/null +++ b/lib/libcapsicum/libcapsicum_grp.c @@ -0,0 +1,426 @@ +/*- + * Copyright (c) 2013 The FreeBSD Foundation + * All rights reserved. + * + * This software was developed by Pawel Jakub Dawidek under sponsorship from + * the FreeBSD Foundation. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <sys/param.h> + +#include <assert.h> +#include <errno.h> +#include <grp.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#include <dnv.h> +#include <nv.h> + +#include "libcapsicum.h" +#include "libcapsicum_grp.h" + +static struct group ggrp; +static char *gbuffer; +static size_t gbufsize; + +static int +group_resize(void) +{ + char *buf; + + if (gbufsize == 0) + gbufsize = 1024; + else + gbufsize *= 2; + + buf = gbuffer; + gbuffer = realloc(buf, gbufsize); + if (gbuffer == NULL) { + free(buf); + gbufsize = 0; + return (ENOMEM); + } + memset(gbuffer, 0, gbufsize); + + return (0); +} + +static int +group_unpack_string(const nvlist_t *nvl, const char *fieldname, char **fieldp, + char **bufferp, size_t *bufsizep) +{ + const char *str; + size_t len; + + str = nvlist_get_string(nvl, fieldname); + len = strlcpy(*bufferp, str, *bufsizep); + if (len >= *bufsizep) + return (ERANGE); + *fieldp = *bufferp; + *bufferp += len + 1; + *bufsizep -= len + 1; + + return (0); +} + +static int +group_unpack_members(const nvlist_t *nvl, char ***fieldp, char **bufferp, + size_t *bufsizep) +{ + const char *mem; + char **outstrs, *str; + size_t nmem, datasize, strsize; + unsigned int ii; + + if (!nvlist_exists_number(nvl, "gr_nmem")) { + datasize = _ALIGNBYTES + sizeof(char *); + if (datasize >= *bufsizep) + return (ERANGE); + outstrs = (char **)_ALIGN(*bufferp); + outstrs[0] = NULL; + *fieldp = outstrs; + *bufferp += datasize; + *bufsizep -= datasize; + return (0); + } + + nmem = (size_t)nvlist_get_number(nvl, "gr_nmem"); + datasize = _ALIGNBYTES + sizeof(char *) * (nmem + 1); + for (ii = 0; ii < nmem; ii++) { + mem = dnvlist_getf_string(nvl, NULL, "gr_mem[%u]", ii); + if (mem == NULL) + return (EINVAL); + datasize += strlen(mem) + 1; + } + + if (datasize >= *bufsizep) + return (ERANGE); + + outstrs = (char **)_ALIGN(*bufferp); + str = (char *)outstrs + sizeof(char *) * (nmem + 1); + for (ii = 0; ii < nmem; ii++) { + mem = nvlist_getf_string(nvl, "gr_mem[%u]", ii); + strsize = strlen(mem) + 1; + memcpy(str, mem, strsize); + outstrs[ii] = str; + str += strsize; + } + assert(ii == nmem); + outstrs[ii] = NULL; + + *fieldp = outstrs; + *bufferp += datasize; + *bufsizep -= datasize; + + return (0); +} + +static int +group_unpack(const nvlist_t *nvl, struct group *grp, char *buffer, + size_t bufsize) +{ + int error; + + if (!nvlist_exists_string(nvl, "gr_name")) + return (EINVAL); + + memset(grp, 0, sizeof(*grp)); + + error = group_unpack_string(nvl, "gr_name", &grp->gr_name, &buffer, + &bufsize); + if (error != 0) + return (error); + error = group_unpack_string(nvl, "gr_passwd", &grp->gr_passwd, &buffer, + &bufsize); + if (error != 0) + return (error); + grp->gr_gid = (gid_t)nvlist_get_number(nvl, "gr_gid"); + error = group_unpack_members(nvl, &grp->gr_mem, &buffer, &bufsize); + if (error != 0) + return (error); + + return (0); +} + +static int +cap_getgrcommon_r(cap_channel_t *chan, const char *cmd, const char *name, + gid_t gid, struct group *grp, char *buffer, size_t bufsize, + struct group **result) +{ + nvlist_t *nvl; + bool getgr_r; + int error; + + nvl = nvlist_create(0); + nvlist_add_string(nvl, "cmd", cmd); + if (strcmp(cmd, "getgrent") == 0 || strcmp(cmd, "getgrent_r") == 0) { + /* Add nothing. */ + } else if (strcmp(cmd, "getgrnam") == 0 || + strcmp(cmd, "getgrnam_r") == 0) { + nvlist_add_string(nvl, "name", name); + } else if (strcmp(cmd, "getgrgid") == 0 || + strcmp(cmd, "getgrgid_r") == 0) { + nvlist_add_number(nvl, "gid", (uint64_t)gid); + } else { + abort(); + } + nvl = cap_xfer_nvlist(chan, nvl); + if (nvl == NULL) { + assert(errno != 0); + *result = NULL; + return (errno); + } + error = (int)nvlist_get_number(nvl, "error"); + if (error != 0) { + nvlist_destroy(nvl); + *result = NULL; + return (error); + } + + if (!nvlist_exists_string(nvl, "gr_name")) { + /* Not found. */ + nvlist_destroy(nvl); + *result = NULL; + return (0); + } + + getgr_r = (strcmp(cmd, "getgrent_r") == 0 || + strcmp(cmd, "getgrnam_r") == 0 || strcmp(cmd, "getgrgid_r") == 0); + + for (;;) { + error = group_unpack(nvl, grp, buffer, bufsize); + if (getgr_r || error != ERANGE) + break; + assert(buffer == gbuffer); + assert(bufsize == gbufsize); + error = group_resize(); + if (error != 0) + break; + /* Update pointers after resize. */ + buffer = gbuffer; + bufsize = gbufsize; + } + + nvlist_destroy(nvl); + + if (error == 0) + *result = grp; + else + *result = NULL; + + return (error); +} + +static struct group * +cap_getgrcommon(cap_channel_t *chan, const char *cmd, const char *name, + gid_t gid) +{ + struct group *result; + int error, serrno; + + serrno = errno; + + error = cap_getgrcommon_r(chan, cmd, name, gid, &ggrp, gbuffer, + gbufsize, &result); + if (error != 0) { + errno = error; + return (NULL); + } + + errno = serrno; + + return (result); +} + +struct group * +cap_getgrent(cap_channel_t *chan) +{ + + return (cap_getgrcommon(chan, "getgrent", NULL, 0)); +} + +struct group * +cap_getgrnam(cap_channel_t *chan, const char *name) +{ + + return (cap_getgrcommon(chan, "getgrnam", name, 0)); +} + +struct group * +cap_getgrgid(cap_channel_t *chan, gid_t gid) +{ + + return (cap_getgrcommon(chan, "getgrgid", NULL, gid)); +} + +int +cap_getgrent_r(cap_channel_t *chan, struct group *grp, char *buffer, + size_t bufsize, struct group **result) +{ + + return (cap_getgrcommon_r(chan, "getgrent_r", NULL, 0, grp, buffer, + bufsize, result)); +} + +int +cap_getgrnam_r(cap_channel_t *chan, const char *name, struct group *grp, + char *buffer, size_t bufsize, struct group **result) +{ + + return (cap_getgrcommon_r(chan, "getgrnam_r", name, 0, grp, buffer, + bufsize, result)); +} + +int +cap_getgrgid_r(cap_channel_t *chan, gid_t gid, struct group *grp, char *buffer, + size_t bufsize, struct group **result) +{ + + return (cap_getgrcommon_r(chan, "getgrgid_r", NULL, gid, grp, buffer, + bufsize, result)); +} + +int +cap_setgroupent(cap_channel_t *chan, int stayopen) +{ + nvlist_t *nvl; + + nvl = nvlist_create(0); + nvlist_add_string(nvl, "cmd", "setgroupent"); + nvlist_add_bool(nvl, "stayopen", stayopen != 0); + nvl = cap_xfer_nvlist(chan, nvl); + if (nvl == NULL) + return (0); + if (nvlist_get_number(nvl, "error") != 0) { + errno = nvlist_get_number(nvl, "error"); + nvlist_destroy(nvl); + return (0); + } + nvlist_destroy(nvl); + + return (1); +} + +int +cap_setgrent(cap_channel_t *chan) +{ + nvlist_t *nvl; + + nvl = nvlist_create(0); + nvlist_add_string(nvl, "cmd", "setgrent"); + nvl = cap_xfer_nvlist(chan, nvl); + if (nvl == NULL) + return (0); + if (nvlist_get_number(nvl, "error") != 0) { + errno = nvlist_get_number(nvl, "error"); + nvlist_destroy(nvl); + return (0); + } + nvlist_destroy(nvl); + + return (1); +} + +void +cap_endgrent(cap_channel_t *chan) +{ + nvlist_t *nvl; + + nvl = nvlist_create(0); + nvlist_add_string(nvl, "cmd", "endgrent"); + /* Ignore any errors, we have no way to report them. */ + nvlist_destroy(cap_xfer_nvlist(chan, nvl)); +} + +int +cap_grp_limit_cmds(cap_channel_t *chan, const char * const *cmds, size_t ncmds) +{ + nvlist_t *limits, *nvl; + unsigned int i; + + if (cap_limit_get(chan, &limits) < 0) + return (-1); + if (limits == NULL) { + limits = nvlist_create(0); + } else { + if (nvlist_exists_nvlist(limits, "cmds")) + nvlist_free_nvlist(limits, "cmds"); + } + nvl = nvlist_create(0); + for (i = 0; i < ncmds; i++) + nvlist_add_null(nvl, cmds[i]); + nvlist_move_nvlist(limits, "cmds", nvl); + return (cap_limit_set(chan, limits)); +} + +int +cap_grp_limit_fields(cap_channel_t *chan, const char * const *fields, + size_t nfields) +{ + nvlist_t *limits, *nvl; + unsigned int i; + + if (cap_limit_get(chan, &limits) < 0) + return (-1); + if (limits == NULL) { + limits = nvlist_create(0); + } else { + if (nvlist_exists_nvlist(limits, "fields")) + nvlist_free_nvlist(limits, "fields"); + } + nvl = nvlist_create(0); + for (i = 0; i < nfields; i++) + nvlist_add_null(nvl, fields[i]); + nvlist_move_nvlist(limits, "fields", nvl); + return (cap_limit_set(chan, limits)); +} + +int +cap_grp_limit_groups(cap_channel_t *chan, const char * const *names, + size_t nnames, gid_t *gids, size_t ngids) +{ + nvlist_t *limits, *groups; + unsigned int i; + + if (cap_limit_get(chan, &limits) < 0) + return (-1); + if (limits == NULL) { + limits = nvlist_create(0); + } else { + if (nvlist_exists_nvlist(limits, "groups")) + nvlist_free_nvlist(limits, "groups"); + } + groups = nvlist_create(0); + for (i = 0; i < ngids; i++) + nvlist_addf_number(groups, (uint64_t)gids[i], "gid%u", i); + for (i = 0; i < nnames; i++) + nvlist_addf_string(groups, names[i], "name%u", i); + nvlist_move_nvlist(limits, "groups", groups); + return (cap_limit_set(chan, limits)); +} |