From 64a5bf3749c67fcc00773a2716d0c7b61b0b4417 Mon Sep 17 00:00:00 2001 From: Niels de Vos Date: Tue, 21 Jul 2015 18:50:12 +0200 Subject: fuse: add "resolve-gids" mount option to overcome 32-groups limit Add a --resolve-gids commandline option to the glusterfs binary. This option gets set when executing "mount -t glusterfs -o resolve-gids ...". This option is most useful in combination with the "acl" mount option. POSIX ACL permission checking is done on the FUSE-client side to improve performance (in addition to the checking on the bricks). The fuse-bridge reads /proc/$PID/status by default, and this file contains maximum 32 groups. Any local (client-side) permission checking that requires more than the first 32 groups will fail. By enabling the "resolve-gids" option, the fuse-bridge will call getgrouplist() to retrieve all the groups from the user accessing the mountpoint. This is comparable to how "nfs.server-aux-gids" works. Note that when a user belongs to more than ~93 groups, the volume option server.manage-gids needs to be enabled too. Without this option, the RPC-layer will need to reduce the number of groups to make them fit in the RPC-header. Change-Id: I7ede90d0e41bcf55755cced5747fa0fb1699edb2 BUG: 1246275 Signed-off-by: Niels de Vos Reviewed-on: http://review.gluster.org/11732 Tested-by: NetBSD Build System Reviewed-by: Ravishankar N Tested-by: Gluster Build System Reviewed-by: jiffin tony Thottan Reviewed-by: Kaleb KEITHLEY --- xlators/mount/fuse/src/fuse-helpers.c | 116 ++++++++++++++++++++++------------ 1 file changed, 77 insertions(+), 39 deletions(-) (limited to 'xlators/mount/fuse/src/fuse-helpers.c') diff --git a/xlators/mount/fuse/src/fuse-helpers.c b/xlators/mount/fuse/src/fuse-helpers.c index 1c888276eb5..22aa9b486d1 100644 --- a/xlators/mount/fuse/src/fuse-helpers.c +++ b/xlators/mount/fuse/src/fuse-helpers.c @@ -20,6 +20,8 @@ #elif defined(CTL_KERN) #include #endif +#include +#include #include "fuse-bridge.h" @@ -146,51 +148,87 @@ void frame_fill_groups (call_frame_t *frame) { #if defined(GF_LINUX_HOST_OS) - char filename[32]; - char line[4096]; - char *ptr = NULL; - FILE *fp = NULL; - int idx = 0; - long int id = 0; - char *saveptr = NULL; - char *endptr = NULL; - int ret = 0; - - ret = snprintf (filename, sizeof filename, "/proc/%d/status", - frame->root->pid); - if (ret >= sizeof filename) - goto out; + xlator_t *this = frame->this; + fuse_private_t *priv = this->private; + char filename[32]; + char line[4096]; + char *ptr = NULL; + FILE *fp = NULL; + int idx = 0; + long int id = 0; + char *saveptr = NULL; + char *endptr = NULL; + int ret = 0; + int ngroups = FUSE_MAX_AUX_GROUPS; + gid_t mygroups[GF_MAX_AUX_GROUPS]; + + if (priv->resolve_gids) { + struct passwd pwent; + char mystrs[1024]; + struct passwd *result; + + if (getpwuid_r (frame->root->uid, &pwent, mystrs, + sizeof(mystrs), &result) != 0) { + gf_log (this->name, GF_LOG_ERROR, "getpwuid_r(%u) " + "failed", frame->root->uid); + return; + } - fp = fopen (filename, "r"); - if (!fp) - goto out; + ngroups = GF_MAX_AUX_GROUPS; + if (getgrouplist (result->pw_name, frame->root->gid, mygroups, + &ngroups) == -1) { + gf_log (this->name, GF_LOG_ERROR, "could not map %s to " + "group list (ngroups %d, max %d)", + result->pw_name, ngroups, GF_MAX_AUX_GROUPS); + return; + } - if (call_stack_alloc_groups (frame->root, FUSE_MAX_AUX_GROUPS) != 0) - goto out; + if (call_stack_alloc_groups (frame->root, ngroups) != 0) + goto out; - while ((ptr = fgets (line, sizeof line, fp))) { - if (strncmp (ptr, "Groups:", 7) != 0) - continue; - - ptr = line + 8; - - for (ptr = strtok_r (ptr, " \t\r\n", &saveptr); - ptr; - ptr = strtok_r (NULL, " \t\r\n", &saveptr)) { - errno = 0; - id = strtol (ptr, &endptr, 0); - if (errno == ERANGE) - break; - if (!endptr || *endptr) - break; - frame->root->groups[idx++] = id; - if (idx == FUSE_MAX_AUX_GROUPS) - break; + /* Copy data to the frame. */ + for (idx = 0; idx < ngroups; ++idx) { + frame->root->groups[idx] = mygroups[idx]; } + frame->root->ngrps = ngroups; + } else { + ret = snprintf (filename, sizeof filename, "/proc/%d/status", + frame->root->pid); + if (ret >= sizeof filename) + goto out; - frame->root->ngrps = idx; - break; + fp = fopen (filename, "r"); + if (!fp) + goto out; + + if (call_stack_alloc_groups (frame->root, ngroups) != 0) + goto out; + + while ((ptr = fgets (line, sizeof line, fp))) { + if (strncmp (ptr, "Groups:", 7) != 0) + continue; + + ptr = line + 8; + + for (ptr = strtok_r (ptr, " \t\r\n", &saveptr); + ptr; + ptr = strtok_r (NULL, " \t\r\n", &saveptr)) { + errno = 0; + id = strtol (ptr, &endptr, 0); + if (errno == ERANGE) + break; + if (!endptr || *endptr) + break; + frame->root->groups[idx++] = id; + if (idx == FUSE_MAX_AUX_GROUPS) + break; + } + + frame->root->ngrps = idx; + break; + } } + out: if (fp) fclose (fp); -- cgit