From ef2e26c91b80556af033d3335e55f5dfa6fff31d Mon Sep 17 00:00:00 2001 From: Andrew Tridgell Date: Wed, 13 Aug 2003 01:53:07 +0000 Subject: first public release of samba4 code (This used to be commit b0510b5428b3461aeb9bbe3cc95f62fc73e2b97f) --- source4/lib/username.c | 537 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 537 insertions(+) create mode 100644 source4/lib/username.c (limited to 'source4/lib/username.c') diff --git a/source4/lib/username.c b/source4/lib/username.c new file mode 100644 index 0000000000..c00ac666d4 --- /dev/null +++ b/source4/lib/username.c @@ -0,0 +1,537 @@ +/* + Unix SMB/CIFS implementation. + Username handling + Copyright (C) Andrew Tridgell 1992-1998 + Copyright (C) Jeremy Allison 1997-2001. + + This program 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. + + This program 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 this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. +*/ + +#include "includes.h" + +/* internal functions */ +static struct passwd *uname_string_combinations(char *s, struct passwd * (*fn) (const char *), int N); +static struct passwd *uname_string_combinations2(char *s, int offset, struct passwd * (*fn) (const char *), int N); + +/***************************************************************** + Check if a user or group name is local (this is a *local* name for + *local* people, there's nothing for you here...). +*****************************************************************/ + +static BOOL name_is_local(const char *name) +{ + return !(strchr_m(name, *lp_winbind_separator())); +} + +/***************************************************************** + Splits passed user or group name to domain and user/group name parts + Returns True if name was splitted and False otherwise. +*****************************************************************/ + +BOOL split_domain_and_name(const char *name, char *domain, char* username) +{ + char *p = strchr(name,*lp_winbind_separator()); + + + /* Parse a string of the form DOMAIN/user into a domain and a user */ + DEBUG(10,("split_domain_and_name: checking whether name |%s| local or not\n", name)); + + if (p) { + fstrcpy(username, p+1); + fstrcpy(domain, name); + domain[PTR_DIFF(p, name)] = 0; + } else if (lp_winbind_use_default_domain()) { + fstrcpy(username, name); + fstrcpy(domain, lp_workgroup()); + } else { + return False; + } + + DEBUG(10,("split_domain_and_name: all is fine, domain is |%s| and name is |%s|\n", domain, username)); + return True; +} + +/**************************************************************************** + Get a users home directory. +****************************************************************************/ + +char *get_user_home_dir(const char *user) +{ + struct passwd *pass; + + /* Ensure the user exists. */ + + pass = Get_Pwnam(user); + + if (!pass) + return(NULL); + /* Return home directory from struct passwd. */ + + return(pass->pw_dir); +} + + +/**************************************************************************** + * A wrapper for sys_getpwnam(). The following variations are tried: + * - as transmitted + * - in all lower case if this differs from transmitted + * - in all upper case if this differs from transmitted + * - using lp_usernamelevel() for permutations. +****************************************************************************/ + +static struct passwd *Get_Pwnam_ret = NULL; + +static struct passwd *Get_Pwnam_internals(const char *user, char *user2) +{ + struct passwd *ret = NULL; + + if (!user2 || !(*user2)) + return(NULL); + + if (!user || !(*user)) + return(NULL); + + /* Try in all lower case first as this is the most + common case on UNIX systems */ + strlower(user2); + DEBUG(5,("Trying _Get_Pwnam(), username as lowercase is %s\n",user2)); + ret = getpwnam_alloc(user2); + if(ret) + goto done; + + /* Try as given, if username wasn't originally lowercase */ + if(strcmp(user, user2) != 0) { + DEBUG(5,("Trying _Get_Pwnam(), username as given is %s\n", user)); + ret = getpwnam_alloc(user); + if(ret) + goto done; + } + + /* Try as uppercase, if username wasn't originally uppercase */ + strupper(user2); + if(strcmp(user, user2) != 0) { + DEBUG(5,("Trying _Get_Pwnam(), username as uppercase is %s\n", user2)); + ret = getpwnam_alloc(user2); + if(ret) + goto done; + } + + /* Try all combinations up to usernamelevel */ + strlower(user2); + DEBUG(5,("Checking combinations of %d uppercase letters in %s\n", lp_usernamelevel(), user2)); + ret = uname_string_combinations(user2, getpwnam_alloc, lp_usernamelevel()); + +done: + DEBUG(5,("Get_Pwnam_internals %s find user [%s]!\n",ret ? "did":"didn't", user)); + + /* This call used to just return the 'passwd' static buffer. + This could then have accidental reuse implications, so + we now malloc a copy, and free it in the next use. + + This should cause the (ab)user to segfault if it + uses an old struct. + + This is better than useing the wrong data in security + critical operations. + + The real fix is to make the callers free the returned + malloc'ed data. + */ + + if (Get_Pwnam_ret) { + passwd_free(&Get_Pwnam_ret); + } + + Get_Pwnam_ret = ret; + + return ret; +} + +/**************************************************************************** + Get_Pwnam wrapper without modification. + NOTE: This with NOT modify 'user'! +****************************************************************************/ + +struct passwd *Get_Pwnam(const char *user) +{ + fstring user2; + struct passwd *ret; + + fstrcpy(user2, user); + + DEBUG(5,("Finding user %s\n", user)); + + ret = Get_Pwnam_internals(user, user2); + + return ret; +} + +/**************************************************************************** + Check if a user is in a netgroup user list. +****************************************************************************/ + +static BOOL user_in_netgroup_list(const char *user, const char *ngname) +{ +#ifdef HAVE_NETGROUP + //static char *mydomain = NULL; + /* REWRITE: make thread safe if caching */ + char *mydomain = NULL; + //if (mydomain == NULL) + yp_get_default_domain(&mydomain); + + if(mydomain == NULL) { + DEBUG(5,("Unable to get default yp domain\n")); + return False; + } + + DEBUG(5,("looking for user %s of domain %s in netgroup %s\n", + user, mydomain, ngname)); + DEBUG(5,("innetgr is %s\n", innetgr(ngname, NULL, user, mydomain) + ? "TRUE" : "FALSE")); + + if (innetgr(ngname, NULL, user, mydomain)) + return (True); +#endif /* HAVE_NETGROUP */ + return False; +} + +/**************************************************************************** + Check if a user is in a winbind group. +****************************************************************************/ + +static BOOL user_in_winbind_group_list(const char *user, const char *gname, BOOL *winbind_answered) +{ + int num_groups; + int i; + gid_t *groups = NULL; + gid_t gid, gid_low, gid_high; + BOOL ret = False; + + *winbind_answered = False; + + if ((gid = nametogid(gname)) == (gid_t)-1) { + DEBUG(0,("user_in_winbind_group_list: nametogid for group %s failed.\n", + gname )); + goto err; + } + + if (!lp_winbind_gid(&gid_low, &gid_high)) { + DEBUG(4, ("winbind gid range not configured, therefore %s cannot be a winbind group\n", gname)); + goto err; + } + + if (gid < gid_low || gid > gid_high) { + DEBUG(4, ("group %s is not a winbind group\n", gname)); + goto err; + } + + /* + * Get the gid's that this user belongs to. + */ + + if ((num_groups = winbind_getgroups(user, 0, NULL)) == -1) + return False; + + if (num_groups == 0) { + *winbind_answered = True; + return False; + } + + if ((groups = (gid_t *)malloc(sizeof(gid_t) * num_groups )) == NULL) { + DEBUG(0,("user_in_winbind_group_list: malloc fail.\n")); + goto err; + } + + if ((num_groups = winbind_getgroups(user, num_groups, groups)) == -1) { + DEBUG(0,("user_in_winbind_group_list: second winbind_getgroups call \ +failed with error %s\n", strerror(errno) )); + goto err; + } + + /* + * Now we have the gid list for this user - convert the gname + * to a gid_t via either winbind or the local UNIX lookup and do the comparison. + */ + + for (i = 0; i < num_groups; i++) { + if (gid == groups[i]) { + ret = True; + break; + } + } + + *winbind_answered = True; + SAFE_FREE(groups); + return ret; + + err: + + *winbind_answered = False; + SAFE_FREE(groups); + return False; +} + +/**************************************************************************** + Check if a user is in a UNIX group. +****************************************************************************/ +static BOOL user_in_unix_group_list(const char *user,const char *gname) +{ + struct passwd *pass = Get_Pwnam(user); + struct sys_userlist *user_list; + struct sys_userlist *member; + TALLOC_CTX *mem_ctx; + + DEBUG(10,("user_in_unix_group_list: checking user %s in group %s\n", user, gname)); + + /* + * We need to check the users primary group as this + * group is implicit and often not listed in the group database. + */ + + mem_ctx = talloc_init("smbgroupedit talloc"); + if (!mem_ctx) return -1; + if (pass) { + if (strequal(gname,gidtoname(mem_ctx, pass->pw_gid))) { + DEBUG(10,("user_in_unix_group_list: group %s is primary group.\n", gname )); + goto exit; + } + } + + user_list = get_users_in_group(gname); + if (user_list == NULL) { + DEBUG(10,("user_in_unix_group_list: no such group %s\n", gname )); + return False; + } + + for (member = user_list; member; member = member->next) { + DEBUG(10,("user_in_unix_group_list: checking user %s against member %s\n", + user, member->unix_name )); + if (strequal(member->unix_name,user)) { + free_userlist(user_list); + goto exit; + } + } + + free_userlist(user_list); + talloc_destroy(mem_ctx); + return False; +exit: + talloc_destroy(mem_ctx); + return True; +} + +/**************************************************************************** + Check if a user is in a group list. Ask winbind first, then use UNIX. +****************************************************************************/ +static BOOL user_in_group_list(const char *user, const char *gname, gid_t *groups, size_t n_groups) +{ + BOOL winbind_answered = False; + BOOL ret; + gid_t gid; + unsigned i; + + gid = nametogid(gname); + if (gid == (gid_t)-1) + return False; + + if (groups && n_groups > 0) { + for (i=0; i < n_groups; i++) { + if (groups[i] == gid) { + return True; + } + } + return False; + } + + /* fallback if we don't yet have the group list */ + + ret = user_in_winbind_group_list(user, gname, &winbind_answered); + if (!winbind_answered) + ret = user_in_unix_group_list(user, gname); + + if (ret) + DEBUG(10,("user_in_group_list: user |%s| is in group |%s|\n", user, gname)); + return ret; +} + +/**************************************************************************** + Check if a user is in a user list - can check combinations of UNIX + and netgroup lists. +****************************************************************************/ + +BOOL user_in_list(const char *user,const char **list, gid_t *groups, size_t n_groups) +{ + if (!list || !*list) + return False; + + DEBUG(10,("user_in_list: checking user %s in list\n", user)); + + while (*list) { + + DEBUG(10,("user_in_list: checking user |%s| against |%s|\n", user, *list)); + + /* + * Check raw username. + */ + if (strequal(user, *list)) + return(True); + + /* + * Now check to see if any combination + * of UNIX and netgroups has been specified. + */ + + if(**list == '@') { + /* + * Old behaviour. Check netgroup list + * followed by UNIX list. + */ + if(user_in_netgroup_list(user, *list +1)) + return True; + if(user_in_group_list(user, *list +1, groups, n_groups)) + return True; + } else if (**list == '+') { + + if((*(*list +1)) == '&') { + /* + * Search UNIX list followed by netgroup. + */ + if(user_in_group_list(user, *list +2, groups, n_groups)) + return True; + if(user_in_netgroup_list(user, *list +2)) + return True; + + } else { + + /* + * Just search UNIX list. + */ + + if(user_in_group_list(user, *list +1, groups, n_groups)) + return True; + } + + } else if (**list == '&') { + + if(*(*list +1) == '+') { + /* + * Search netgroup list followed by UNIX list. + */ + if(user_in_netgroup_list(user, *list +2)) + return True; + if(user_in_group_list(user, *list +2, groups, n_groups)) + return True; + } else { + /* + * Just search netgroup list. + */ + if(user_in_netgroup_list(user, *list +1)) + return True; + } + } else if (!name_is_local(*list)) { + /* + * If user name did not match and token is not + * a unix group and the token has a winbind separator in the + * name then see if it is a Windows group. + */ + + DOM_SID g_sid; + enum SID_NAME_USE name_type; + BOOL winbind_answered = False; + BOOL ret; + fstring groupname, domain; + + /* Parse a string of the form DOMAIN/user into a domain and a user */ + + char *p = strchr(*list,*lp_winbind_separator()); + + DEBUG(10,("user_in_list: checking if user |%s| is in winbind group |%s|\n", user, *list)); + + if (p) { + fstrcpy(groupname, p+1); + fstrcpy(domain, *list); + domain[PTR_DIFF(p, *list)] = 0; + + /* Check to see if name is a Windows group */ + if (winbind_lookup_name(domain, groupname, &g_sid, &name_type) && name_type == SID_NAME_DOM_GRP) { + + /* Check if user name is in the Windows group */ + ret = user_in_winbind_group_list(user, *list, &winbind_answered); + + if (winbind_answered && ret == True) { + DEBUG(10,("user_in_list: user |%s| is in winbind group |%s|\n", user, *list)); + return ret; + } + } + } + } + + list++; + } + return(False); +} + +/* The functions below have been taken from password.c and slightly modified */ +/**************************************************************************** + Apply a function to upper/lower case combinations + of a string and return true if one of them returns true. + Try all combinations with N uppercase letters. + offset is the first char to try and change (start with 0) + it assumes the string starts lowercased +****************************************************************************/ + +static struct passwd *uname_string_combinations2(char *s,int offset,struct passwd *(*fn)(const char *),int N) +{ + ssize_t len = (ssize_t)strlen(s); + int i; + struct passwd *ret; + + if (N <= 0 || offset >= len) + return(fn(s)); + + for (i=offset;i<(len-(N-1));i++) { + char c = s[i]; + if (!islower((int)c)) + continue; + s[i] = toupper(c); + ret = uname_string_combinations2(s,i+1,fn,N-1); + if(ret) + return(ret); + s[i] = c; + } + return(NULL); +} + +/**************************************************************************** + Apply a function to upper/lower case combinations + of a string and return true if one of them returns true. + Try all combinations with up to N uppercase letters. + offset is the first char to try and change (start with 0) + it assumes the string starts lowercased +****************************************************************************/ + +static struct passwd * uname_string_combinations(char *s,struct passwd * (*fn)(const char *),int N) +{ + int n; + struct passwd *ret; + + for (n=1;n<=N;n++) { + ret = uname_string_combinations2(s,0,fn,n); + if(ret) + return(ret); + } + return(NULL); +} + -- cgit