/*- * Copyright (c) 1997-2000 Doug Rabson * All rights reserved. * * 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 AUTHOR 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 AUTHOR 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. * * $FreeBSD: head/sys/kern/kern_linker.c 70417 2000-12-28 08:14:58Z peter $ */ #include "opt_ddb.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "linker_if.h" #ifdef KLD_DEBUG int kld_debug = 0; #endif static char *linker_search_path(const char *name); static const char *linker_basename(const char* path); MALLOC_DEFINE(M_LINKER, "linker", "kernel linker"); linker_file_t linker_kernel_file; static struct lock lock; /* lock for the file list */ static linker_class_list_t classes; static linker_file_list_t linker_files; static int next_file_id = 1; /* XXX wrong name; we're looking at version provision tags here, not modules */ typedef TAILQ_HEAD(, modlist) modlisthead_t; struct modlist { TAILQ_ENTRY(modlist) link; /* chain together all modules */ linker_file_t container; const char *name; }; typedef struct modlist *modlist_t; static modlisthead_t found_modules; static char * linker_strdup(const char *str) { char *result; if ((result = malloc((strlen(str) + 1), M_LINKER, M_WAITOK)) != NULL) strcpy(result, str); return(result); } static void linker_init(void* arg) { lockinit(&lock, PVM, "klink", 0, 0); TAILQ_INIT(&classes); TAILQ_INIT(&linker_files); } SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, 0); int linker_add_class(linker_class_t lc) { kobj_class_compile((kobj_class_t) lc); TAILQ_INSERT_TAIL(&classes, lc, link); return 0; } static void linker_file_sysinit(linker_file_t lf) { struct linker_set* sysinits; struct sysinit** sipp; struct sysinit** xipp; struct sysinit* save; KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n", lf->filename)); sysinits = (struct linker_set*) linker_file_lookup_symbol(lf, "sysinit_set", 0); KLD_DPF(FILE, ("linker_file_sysinit: SYSINITs %p\n", sysinits)); if (!sysinits) return; /* * Perform a bubble sort of the system initialization objects by * their subsystem (primary key) and order (secondary key). * * Since some things care about execution order, this is the * operation which ensures continued function. */ for (sipp = (struct sysinit **)sysinits->ls_items; *sipp; sipp++) { for (xipp = sipp + 1; *xipp; xipp++) { if ((*sipp)->subsystem < (*xipp)->subsystem || ((*sipp)->subsystem == (*xipp)->subsystem && (*sipp)->order <= (*xipp)->order)) continue; /* skip*/ save = *sipp; *sipp = *xipp; *xipp = save; } } /* * Traverse the (now) ordered list of system initialization tasks. * Perform each task, and continue on to the next task. */ for (sipp = (struct sysinit **)sysinits->ls_items; *sipp; sipp++) { if ((*sipp)->subsystem == SI_SUB_DUMMY) continue; /* skip dummy task(s)*/ /* Call function */ (*((*sipp)->func))((*sipp)->udata); } } static void linker_file_sysuninit(linker_file_t lf) { struct linker_set* sysuninits; struct sysinit** sipp; struct sysinit** xipp; struct sysinit* save; KLD_DPF(FILE, ("linker_file_sysuninit: calling SYSUNINITs for %s\n", lf->filename)); sysuninits = (struct linker_set*) linker_file_lookup_symbol(lf, "sysuninit_set", 0); KLD_DPF(FILE, ("linker_file_sysuninit: SYSUNINITs %p\n", sysuninits)); if (!sysuninits) return; /* * Perform a reverse bubble sort of the system initialization objects * by their subsystem (primary key) and order (secondary key). * * Since some things care about execution order, this is the * operation which ensures continued function. */ for (sipp = (struct sysinit **)sysuninits->ls_items; *sipp; sipp++) { for (xipp = sipp + 1; *xipp; xipp++) { if ((*sipp)->subsystem > (*xipp)->subsystem || ((*sipp)->subsystem == (*xipp)->subsystem && (*sipp)->order >= (*xipp)->order)) continue; /* skip*/ save = *sipp; *sipp = *xipp; *xipp = save; } } /* * Traverse the (now) ordered list of system initialization tasks. * Perform each task, and continue on to the next task. */ for (sipp = (struct sysinit **)sysuninits->ls_items; *sipp; sipp++) { if ((*sipp)->subsystem == SI_SUB_DUMMY) continue; /* skip dummy task(s)*/ /* Call function */ (*((*sipp)->func))((*sipp)->udata); } } static void linker_file_register_sysctls(linker_file_t lf) { struct linker_set* sysctls; KLD_DPF(FILE, ("linker_file_register_sysctls: registering SYSCTLs for %s\n", lf->filename)); sysctls = (struct linker_set*) linker_file_lookup_symbol(lf, "sysctl_set", 0); KLD_DPF(FILE, ("linker_file_register_sysctls: SYSCTLs %p\n", sysctls)); if (!sysctls) return; sysctl_register_set(sysctls); } static void linker_file_unregister_sysctls(linker_file_t lf) { struct linker_set* sysctls; KLD_DPF(FILE, ("linker_file_unregister_sysctls: registering SYSCTLs for %s\n", lf->filename)); sysctls = (struct linker_set*) linker_file_lookup_symbol(lf, "sysctl_set", 0); KLD_DPF(FILE, ("linker_file_unregister_sysctls: SYSCTLs %p\n", sysctls)); if (!sysctls) return; sysctl_unregister_set(sysctls); } extern struct linker_set modmetadata_set; static int linker_file_register_modules(linker_file_t lf) { int error, mcount; struct linker_set *modules; struct mod_metadata **mdpp; const moduledata_t *moddata; struct sysinit **sipp; KLD_DPF(FILE, ("linker_file_register_modules: registering modules in %s\n", lf->filename)); modules = (struct linker_set*) linker_file_lookup_symbol(lf, "modmetadata_set", 0); if (!modules && lf == linker_kernel_file) modules = &modmetadata_set; mcount = 0; if (modules) { for (mdpp = (struct mod_metadata**)modules->ls_items; *mdpp; mdpp++) { if ((*mdpp)->md_type != MDT_MODULE) continue; mcount++; moddata = (*mdpp)->md_data; KLD_DPF(FILE, ("Registering module %s in %s\n", moddata->name, lf->filename)); error = module_register(moddata, lf); if (error) printf("Module %s failed to register: %d\n", moddata->name, error); } } if (mcount) return mcount; /* Do not mix old and new style */ /* Hack - handle old kld's without metadata */ modules = (struct linker_set*) linker_file_lookup_symbol(lf, "sysinit_set", 0); if (modules) { for (sipp = (struct sysinit **)modules->ls_items; *sipp; sipp++) { if ((*sipp)->func != module_register_init) continue; mcount++; moddata = (*sipp)->udata; printf("Old-style KLD file %s found\n", moddata->name); error = module_register(moddata, lf); if (error) printf("Old-style KLD file %s failed to register: %d\n", moddata->name, error); } } return mcount; } static void linker_init_kernel_modules(void) { linker_file_register_modules(linker_kernel_file); } SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules, 0); int linker_load_file(const char* filename, linker_file_t* result) { linker_class_t lc; linker_file_t lf; int foundfile, error = 0; /* Refuse to load modules if securelevel raised */ if (securelevel > 0) return EPERM; lf = linker_find_file_by_name(filename); if (lf) { KLD_DPF(FILE, ("linker_load_file: file %s is already loaded, incrementing refs\n", filename)); *result = lf; lf->refs++; goto out; } lf = NULL; foundfile = 0; for (lc = TAILQ_FIRST(&classes); lc; lc = TAILQ_NEXT(lc, link)) { KLD_DPF(FILE, ("linker_load_file: trying to load %s as %s\n", filename, lc->desc)); error = LINKER_LOAD_FILE(lc, filename, &lf); /* * If we got something other than ENOENT, then it exists but we cannot * load it for some other reason. */ if (error != ENOENT) foundfile = 1; if (lf) { linker_file_register_modules(lf); linker_file_register_sysctls(lf); linker_file_sysinit(lf); lf->flags |= LINKER_FILE_LINKED; *result = lf; error = 0; goto out; } } /* * Less than ideal, but tells the user whether it failed to load or * the module was not found. */ if (foundfile) error = ENOEXEC; /* Format not recognised (or unloadable) */ else error = ENOENT; /* Nothing found */ out: return error; } linker_file_t linker_find_file_by_name(const char* filename) { linker_file_t lf = 0; char *koname; koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK); if (koname == NULL) goto out; sprintf(koname, "%s.ko", filename); lockmgr(&lock, LK_SHARED, 0, curproc); for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) { if (!strcmp(lf->filename, koname)) break; if (!strcmp(lf->filename, filename)) break; } lockmgr(&lock, LK_RELEASE, 0, curproc); out: if (koname) free(koname, M_LINKER); return lf; } linker_file_t linker_find_file_by_id(int fileid) { linker_file_t lf = 0; lockmgr(&lock, LK_SHARED, 0, curproc); for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) if (lf->id == fileid) break; lockmgr(&lock, LK_RELEASE, 0, curproc); return lf; } linker_file_t linker_make_file(const char* pathname, linker_class_t lc) { linker_file_t lf = 0; const char *filename; filename = linker_basename(pathname); KLD_DPF(FILE, ("linker_make_file: new file, filename=%s\n", filename)); lockmgr(&lock, LK_EXCLUSIVE, 0, curproc); lf = (linker_file_t) kobj_create((kobj_class_t) lc, M_LINKER, M_WAITOK); if (!lf) goto out; lf->refs = 1; lf->userrefs = 0; lf->flags = 0; lf->filename = linker_strdup(filename); lf->id = next_file_id++; lf->ndeps = 0; lf->deps = NULL; STAILQ_INIT(&lf->common); TAILQ_INIT(&lf->modules); TAILQ_INSERT_TAIL(&linker_files, lf, link); out: lockmgr(&lock, LK_RELEASE, 0, curproc); return lf; } int linker_file_unload(linker_file_t file) { module_t mod, next; modlist_t ml, nextml; struct common_symbol* cp; int error = 0; int i; /* Refuse to unload modules if securelevel raised */ if (securelevel > 0) return EPERM; KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs)); lockmgr(&lock, LK_EXCLUSIVE, 0, curproc); if (file->refs == 1) { KLD_DPF(FILE, ("linker_file_unload: file is unloading, informing modules\n")); /* * Inform any modules associated with this file. */ for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) { next = module_getfnext(mod); /* * Give the module a chance to veto the unload. */ if ((error = module_unload(mod)) != 0) { KLD_DPF(FILE, ("linker_file_unload: module %x vetoes unload\n", mod)); lockmgr(&lock, LK_RELEASE, 0, curproc); goto out; } module_release(mod); } } file->refs--; if (file->refs > 0) { lockmgr(&lock, LK_RELEASE, 0, curproc); goto out; } for (ml = TAILQ_FIRST(&found_modules); ml; ml = nextml) { nextml = TAILQ_NEXT(ml, link); if (ml->container == file) { TAILQ_REMOVE(&found_modules, ml, link); } } /* Don't try to run SYSUNINITs if we are unloaded due to a link error */ if (file->flags & LINKER_FILE_LINKED) { linker_file_sysuninit(file); linker_file_unregister_sysctls(file); } TAILQ_REMOVE(&linker_files, file, link); lockmgr(&lock, LK_RELEASE, 0, curproc); if (file->deps) { for (i = 0; i < file->ndeps; i++) linker_file_unload(file->deps[i]); free(file->deps, M_LINKER); file->deps = NULL; } for (cp = STAILQ_FIRST(&file->common); cp; cp = STAILQ_FIRST(&file->common)) { STAILQ_REMOVE(&file->common, cp, common_symbol, link); free(cp, M_LINKER); } LINKER_UNLOAD(file); if (file->filename) { free(file->filename, M_LINKER); file->filename = NULL; } kobj_delete((kobj_t) file, M_LINKER); out: return error; } int linker_file_add_dependancy(linker_file_t file, linker_file_t dep) { linker_file_t* newdeps; newdeps = malloc((file->ndeps + 1) * sizeof(linker_file_t*), M_LINKER, M_WAITOK | M_ZERO); if (newdeps == NULL) return ENOMEM; if (file->deps) { bcopy(file->deps, newdeps, file->ndeps * sizeof(linker_file_t*)); free(file->deps, M_LINKER); } file->deps = newdeps; file->deps[file->ndeps] = dep; file->ndeps++; return 0; } caddr_t linker_file_lookup_symbol(linker_file_t file, const char* name, int deps) { c_linker_sym_t sym; linker_symval_t symval; caddr_t address; size_t common_size = 0; int i; KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%x, name=%s, deps=%d\n", file, name, deps)); if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) { LINKER_SYMBOL_VALUES(file, sym, &symval); if (symval.value == 0) /* * For commons, first look them up in the dependancies and * only allocate space if not found there. */ common_size = symval.size; else { KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol.value=%x\n", symval.value)); return symval.value; } } if (deps) { for (i = 0; i < file->ndeps; i++) { address = linker_file_lookup_symbol(file->deps[i], name, 0); if (address) { KLD_DPF(SYM, ("linker_file_lookup_symbol: deps value=%x\n", address)); return address; } } } if (common_size > 0) { /* * This is a common symbol which was not found in the * dependancies. We maintain a simple common symbol table in * the file object. */ struct common_symbol* cp; for (cp = STAILQ_FIRST(&file->common); cp; cp = STAILQ_NEXT(cp, link)) if (!strcmp(cp->name, name)) { KLD_DPF(SYM, ("linker_file_lookup_symbol: old common value=%x\n", cp->address)); return cp->address; } /* * Round the symbol size up to align. */ common_size = (common_size + sizeof(int) - 1) & -sizeof(int); cp = malloc(sizeof(struct common_symbol) + common_size + strlen(name) + 1, M_LINKER, M_WAITOK | M_ZERO); if (!cp) { KLD_DPF(SYM, ("linker_file_lookup_symbol: nomem\n")); return 0; } cp->address = (caddr_t) (cp + 1); cp->name = cp->address + common_size; strcpy(cp->name, name); bzero(cp->address, common_size); STAILQ_INSERT_TAIL(&file->common, cp, link); KLD_DPF(SYM, ("linker_file_lookup_symbol: new common value=%x\n", cp->address)); return cp->address; } KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); return 0; } #ifdef DDB /* * DDB Helpers. DDB has to look across multiple files with their own * symbol tables and string tables. * * Note that we do not obey list locking protocols here. We really don't * need DDB to hang because somebody's got the lock held. We'll take the * chance that the files list is inconsistant instead. */ int linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) { linker_file_t lf; for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) { if (LINKER_LOOKUP_SYMBOL(lf, symstr, sym) == 0) return 0; } return ENOENT; } int linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) { linker_file_t lf; u_long off = (uintptr_t)value; u_long diff, bestdiff; c_linker_sym_t best; c_linker_sym_t es; best = 0; bestdiff = off; for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) { if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0) continue; if (es != 0 && diff < bestdiff) { best = es; bestdiff = diff; } if (bestdiff == 0) break; } if (best) { *sym = best; *diffp = bestdiff; return 0; } else { *sym = 0; *diffp = off; return ENOENT; } } int linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) { linker_file_t lf; for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) { if (LINKER_SYMBOL_VALUES(lf, sym, symval) == 0) return 0; } return ENOENT; } #endif /* * Syscalls. */ int kldload(struct proc* p, struct kldload_args* uap) { char* pathname, *realpath; const char *filename; linker_file_t lf; int error = 0; p->p_retval[0] = -1; if (securelevel > 0) /* redundant, but that's OK */ return EPERM; if ((error = suser(p)) != 0) return error; realpath = NULL; pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); if ((error = copyinstr(SCARG(uap, file), pathname, MAXPATHLEN, NULL)) != 0) goto out; realpath = linker_search_path(pathname); if (realpath == NULL) { error = ENOENT; goto out; } /* Can't load more than one file with the same name */ filename = linker_basename(realpath); if (linker_find_file_by_name(filename)) { error = EEXIST; goto out; } if ((error = linker_load_file(realpath, &lf)) != 0) goto out; lf->userrefs++; p->p_retval[0] = lf->id; out: if (pathname) free(pathname, M_TEMP); if (realpath) free(realpath, M_LINKER); return error; } int kldunload(struct proc* p, struct kldunload_args* uap) { linker_file_t lf; int error = 0; if (securelevel > 0) /* redundant, but that's OK */ return EPERM; if ((error = suser(p)) != 0) return error; lf = linker_find_file_by_id(SCARG(uap, fileid)); if (lf) { KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); if (lf->userrefs == 0) { printf("kldunload: attempt to unload file that was loaded by the kernel\n"); error = EBUSY; goto out; } lf->userrefs--; error = linker_file_unload(lf); if (error) lf->userrefs++; } else error = ENOENT; out: return error; } int kldfind(struct proc* p, struct kldfind_args* uap) { char* pathname; const char *filename; linker_file_t lf; int error = 0; p->p_retval[0] = -1; pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); if ((error = copyinstr(SCARG(uap, file), pathname, MAXPATHLEN, NULL)) != 0) goto out; filename = linker_basename(pathname); lf = linker_find_file_by_name(filename); if (lf) p->p_retval[0] = lf->id; else error = ENOENT; out: if (pathname) free(pathname, M_TEMP); return error; } int kldnext(struct proc* p, struct kldnext_args* uap) { linker_file_t lf; int error = 0; if (SCARG(uap, fileid) == 0) { if (TAILQ_FIRST(&linker_files)) p->p_retval[0] = TAILQ_FIRST(&linker_files)->id; else p->p_retval[0] = 0; return 0; } lf = linker_find_file_by_id(SCARG(uap, fileid)); if (lf) { if (TAILQ_NEXT(lf, link)) p->p_retval[0] = TAILQ_NEXT(lf, link)->id; else p->p_retval[0] = 0; } else error = ENOENT; return error; } int kldstat(struct proc* p, struct kldstat_args* uap) { linker_file_t lf; int error = 0; int version; struct kld_file_stat* stat; int namelen; lf = linker_find_file_by_id(SCARG(uap, fileid)); if (!lf) { error = ENOENT; goto out; } stat = SCARG(uap, stat); /* * Check the version of the user's structure. */ if ((error = copyin(&stat->version, &version, sizeof(version))) != 0) goto out; if (version != sizeof(struct kld_file_stat)) { error = EINVAL; goto out; } namelen = strlen(lf->filename) + 1; if (namelen > MAXPATHLEN) namelen = MAXPATHLEN; if ((error = copyout(lf->filename, &stat->name[0], namelen)) != 0) goto out; if ((error = copyout(&lf->refs, &stat->refs, sizeof(int))) != 0) goto out; if ((error = copyout(&lf->id, &stat->id, sizeof(int))) != 0) goto out; if ((error = copyout(&lf->address, &stat->address, sizeof(caddr_t))) != 0) goto out; if ((error = copyout(&lf->size, &stat->size, sizeof(size_t))) != 0) goto out; p->p_retval[0] = 0; out: return error; } int kldfirstmod(struct proc* p, struct kldfirstmod_args* uap) { linker_file_t lf; int error = 0; lf = linker_find_file_by_id(SCARG(uap, fileid)); if (lf) { if (TAILQ_FIRST(&lf->modules)) p->p_retval[0] = module_getid(TAILQ_FIRST(&lf->modules)); else p->p_retval[0] = 0; } else error = ENOENT; return error; } int kldsym(struct proc *p, struct kldsym_args *uap) { char *symstr = NULL; c_linker_sym_t sym; linker_symval_t symval; linker_file_t lf; struct kld_sym_lookup lookup; int error = 0; if ((error = copyin(SCARG(uap, data), &lookup, sizeof(lookup))) != 0) goto out; if (lookup.version != sizeof(lookup) || SCARG(uap, cmd) != KLDSYM_LOOKUP) { error = EINVAL; goto out; } symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) goto out; if (SCARG(uap, fileid) != 0) { lf = linker_find_file_by_id(SCARG(uap, fileid)); if (lf == NULL) { error = ENOENT; goto out; } if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { lookup.symvalue = (uintptr_t)symval.value; lookup.symsize = symval.size; error = copyout(&lookup, SCARG(uap, data), sizeof(lookup)); } else error = ENOENT; } else { for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) { if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { lookup.symvalue = (uintptr_t)symval.value; lookup.symsize = symval.size; error = copyout(&lookup, SCARG(uap, data), sizeof(lookup)); break; } } if (!lf) error = ENOENT; } out: if (symstr) free(symstr, M_TEMP); return error; } /* * Preloaded module support */ static modlist_t modlist_lookup(const char *name) { modlist_t mod; for (mod = TAILQ_FIRST(&found_modules); mod; mod = TAILQ_NEXT(mod, link)) { if (!strcmp(mod->name, name)) return mod; } return NULL; } /* * This routine is cheap and nasty but will work for data pointers. */ static void * linker_reloc_ptr(linker_file_t lf, void *offset) { return lf->address + (uintptr_t)offset; } static void linker_preload(void* arg) { caddr_t modptr; char *modname, *nmodname; char *modtype; linker_file_t lf; linker_class_t lc; int error, mcount; struct linker_set *sysinits; linker_file_list_t loaded_files; linker_file_list_t depended_files; struct linker_set *deps; struct mod_metadata *mp, *nmp; int i, j; int resolves; modlist_t mod; TAILQ_INIT(&loaded_files); TAILQ_INIT(&depended_files); TAILQ_INIT(&found_modules); error = 0; modptr = NULL; while ((modptr = preload_search_next_name(modptr)) != NULL) { modname = (char *)preload_search_info(modptr, MODINFO_NAME); modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); if (modname == NULL) { printf("Preloaded module at %p does not have a name!\n", modptr); continue; } if (modtype == NULL) { printf("Preloaded module at %p does not have a type!\n", modptr); continue; } printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, modptr); lf = NULL; for (lc = TAILQ_FIRST(&classes); lc; lc = TAILQ_NEXT(lc, link)) { error = LINKER_LINK_PRELOAD(lc, modname, &lf); if (error) { lf = NULL; break; } } if (lf) TAILQ_INSERT_TAIL(&loaded_files, lf, loaded); } /* * First get a list of stuff in the kernel. */ deps = (struct linker_set*) linker_file_lookup_symbol(linker_kernel_file, MDT_SETNAME, 0); if (deps) { for (i = 0; i < deps->ls_length; i++) { mp = deps->ls_items[i]; if (mp->md_type != MDT_VERSION) continue; modname = mp->md_cval; if (modlist_lookup(modname) != NULL) { printf("module %s already present!\n", modname); /* XXX what can we do? this is a build error. :-( */ continue; } mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT|M_ZERO); if (mod == NULL) panic("no memory for module list"); mod->container = linker_kernel_file; mod->name = modname; TAILQ_INSERT_TAIL(&found_modules, mod, link); } } /* * this is a once-off kinky bubble sort * resolve relocation dependency requirements */ restart: for (lf = TAILQ_FIRST(&loaded_files); lf; lf = TAILQ_NEXT(lf, loaded)) { deps = (struct linker_set*) linker_file_lookup_symbol(lf, MDT_SETNAME, 0); /* * First, look to see if we would successfully link with this stuff. */ resolves = 1; /* unless we know otherwise */ if (deps) { for (i = 0; i < deps->ls_length; i++) { mp = linker_reloc_ptr(lf, deps->ls_items[i]); if (mp->md_type != MDT_DEPEND) continue; modname = linker_reloc_ptr(lf, mp->md_cval); for (j = 0; j < deps->ls_length; j++) { nmp = linker_reloc_ptr(lf, deps->ls_items[j]); if (nmp->md_type != MDT_VERSION) continue; nmodname = linker_reloc_ptr(lf, nmp->md_cval); if (strcmp(modname, nmodname) == 0) break; } if (j < deps->ls_length) /* it's a self reference */ continue; if (modlist_lookup(modname) == NULL) { /* ok, the module isn't here yet, we are not finished */ resolves = 0; } } } /* * OK, if we found our modules, we can link. So, "provide" the * modules inside and add it to the end of the link order list. */ if (resolves) { if (deps) { for (i = 0; i < deps->ls_length; i++) { mp = linker_reloc_ptr(lf, deps->ls_items[i]); if (mp->md_type != MDT_VERSION) continue; modname = linker_reloc_ptr(lf, mp->md_cval); if (modlist_lookup(modname) != NULL) { printf("module %s already present!\n", modname); linker_file_unload(lf); TAILQ_REMOVE(&loaded_files, lf, loaded); goto restart; /* we changed the tailq next ptr */ } mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT|M_ZERO); if (mod == NULL) panic("no memory for module list"); mod->container = lf; mod->name = modname; TAILQ_INSERT_TAIL(&found_modules, mod, link); } } TAILQ_REMOVE(&loaded_files, lf, loaded); TAILQ_INSERT_TAIL(&depended_files, lf, loaded); /* * Since we provided modules, we need to restart the sort so * that the previous files that depend on us have a chance. * Also, we've busted the tailq next pointer with the REMOVE. */ goto restart; } } /* * At this point, we check to see what could not be resolved.. */ for (lf = TAILQ_FIRST(&loaded_files); lf; lf = TAILQ_NEXT(lf, loaded)) { printf("KLD file %s is missing dependencies\n", lf->filename); linker_file_unload(lf); TAILQ_REMOVE(&loaded_files, lf, loaded); } /* * We made it. Finish off the linking in the order we determined. */ for (lf = TAILQ_FIRST(&depended_files); lf; lf = TAILQ_NEXT(lf, loaded)) { if (linker_kernel_file) { linker_kernel_file->refs++; error = linker_file_add_dependancy(lf, linker_kernel_file); if (error) panic("cannot add dependency"); } lf->userrefs++; /* so we can (try to) kldunload it */ deps = (struct linker_set*) linker_file_lookup_symbol(lf, MDT_SETNAME, 0); if (deps) { for (i = 0; i < deps->ls_length; i++) { mp = linker_reloc_ptr(lf, deps->ls_items[i]); if (mp->md_type != MDT_DEPEND) continue; modname = linker_reloc_ptr(lf, mp->md_cval); mod = modlist_lookup(modname); mod->container->refs++; error = linker_file_add_dependancy(lf, mod->container); if (error) panic("cannot add dependency"); } } /* Now do relocation etc using the symbol search paths established by the dependencies */ error = LINKER_LINK_PRELOAD_FINISH(lf); if (error) { printf("KLD file %s - could not finalize loading\n", lf->filename); linker_file_unload(lf); continue; } mcount = linker_file_register_modules(lf); sysinits = (struct linker_set*) linker_file_lookup_symbol(lf, "sysinit_set", 0); if (sysinits) sysinit_add((struct sysinit **)sysinits->ls_items); linker_file_register_sysctls(lf); lf->flags |= LINKER_FILE_LINKED; } /* woohoo! we made it! */ } SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, 0); /* * Search for a not-loaded module by name. * * Modules may be found in the following locations: * * - preloaded (result is just the module name) * - on disk (result is full path to module) * * If the module name is qualified in any way (contains path, etc.) * the we simply return a copy of it. * * The search path can be manipulated via sysctl. Note that we use the ';' * character as a separator to be consistent with the bootloader. */ static char def_linker_path[] = "/boot/modules/;/modules/;/boot/kernel/"; static char linker_path[MAXPATHLEN] = ""; SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path, sizeof(linker_path), "module load search path"); TUNABLE_STR_DECL("module_path", def_linker_path, linker_path, sizeof(linker_path)); static char *linker_ext_list[] = { ".ko", "", NULL }; static char * linker_search_path(const char *name) { struct nameidata nd; struct proc *p = curproc; /* XXX */ char *cp, *ep, *result, **cpp; int error, extlen, len, flags; enum vtype type; /* qualified at all? */ if (index(name, '/')) return(linker_strdup(name)); extlen = 0; for (cpp = linker_ext_list; *cpp; cpp++) { len = strlen(*cpp); if (len > extlen) extlen = len; } extlen++; /* trailing '\0' */ /* traverse the linker path */ cp = linker_path; len = strlen(name); for (;;) { /* find the end of this component */ for (ep = cp; (*ep != 0) && (*ep != ';'); ep++) ; result = malloc((len + (ep - cp) + extlen + 1), M_LINKER, M_WAITOK); if (result == NULL) /* actually ENOMEM */ return(NULL); for (cpp = linker_ext_list; *cpp; cpp++) { strncpy(result, cp, ep - cp); strcpy(result + (ep - cp), "/"); strcat(result, name); strcat(result, *cpp); /* * Attempt to open the file, and return the path if we succeed * and it's a regular file. */ NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, result, p); flags = FREAD; error = vn_open(&nd, &flags, 0); if (error == 0) { NDFREE(&nd, NDF_ONLY_PNBUF); type = nd.ni_vp->v_type; VOP_UNLOCK(nd.ni_vp, 0, p); vn_close(nd.ni_vp, FREAD, p->p_ucred, p); if (type == VREG) return(result); } } free(result, M_LINKER); if (*ep == 0) break; cp = ep + 1; } return(NULL); } static const char * linker_basename(const char* path) { const char *filename; filename = rindex(path, '/'); if (filename == NULL) return path; if (filename[1]) filename++; return filename; } /* * Find a file which contains given module and load it, * if "parent" is not NULL, register a reference to it. */ static int linker_load_module(const char *modname, struct linker_file *parent) { linker_file_t lfdep; const char *filename; char *pathname; int error; /* * There will be a system to look up or guess a file name from * a module name. * For now we just try to load a file with the same name. */ pathname = linker_search_path(modname); if (pathname == NULL) return ENOENT; /* Can't load more than one file with the same basename */ filename = linker_basename(pathname); if (linker_find_file_by_name(filename)) { error = EEXIST; goto out; } do { error = linker_load_file(pathname, &lfdep); if (error) break; if (parent) { error = linker_file_add_dependancy(parent, lfdep); if (error) break; } } while(0); out: if (pathname) free(pathname, M_LINKER); return error; } /* * This routine is responsible for finding dependencies of userland * initiated kldload(2)'s of files. */ int linker_load_dependancies(linker_file_t lf) { linker_file_t lfdep; struct linker_set *deps; struct mod_metadata *mp, *nmp; modlist_t mod; char *modname, *nmodname; int i, j, error = 0; /* * All files are dependant on /kernel. */ if (linker_kernel_file) { linker_kernel_file->refs++; error = linker_file_add_dependancy(lf, linker_kernel_file); if (error) return error; } deps = (struct linker_set*) linker_file_lookup_symbol(lf, MDT_SETNAME, 0); if (deps != NULL) { for (i = 0; i < deps->ls_length; i++) { mp = linker_reloc_ptr(lf, deps->ls_items[i]); if (mp->md_type != MDT_VERSION) continue; modname = linker_reloc_ptr(lf, mp->md_cval); if (modlist_lookup(modname) != NULL) { printf("module %s already present!\n", modname); return EEXIST; } } } if (deps != NULL) { for (i = 0; i < deps->ls_length; i++) { mp = linker_reloc_ptr(lf, deps->ls_items[i]); if (mp->md_type != MDT_DEPEND) continue; modname = linker_reloc_ptr(lf, mp->md_cval); nmodname = NULL; for (j = 0; j < deps->ls_length; j++) { nmp = linker_reloc_ptr(lf, deps->ls_items[j]); if (nmp->md_type != MDT_VERSION) continue; nmodname = linker_reloc_ptr(lf, nmp->md_cval); if (strcmp(modname, nmodname) == 0) break; } if (j < deps->ls_length) /* early exit, it's a self reference */ continue; mod = modlist_lookup(modname); if (mod) { /* woohoo, it's loaded already */ lfdep = mod->container; lfdep->refs++; error = linker_file_add_dependancy(lf, lfdep); if (error) break; continue; } error = linker_load_module(modname, lf); if (error) { printf("KLD %s: depends on %s - not available\n", lf->filename, modname); break; } } } if (error == 0 && deps) { for (i = 0; i < deps->ls_length; i++) { mp = linker_reloc_ptr(lf, deps->ls_items[i]); if (mp->md_type != MDT_VERSION) continue; modname = linker_reloc_ptr(lf, mp->md_cval); mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT|M_ZERO); if (mod == NULL) panic("no memory for module list"); mod->container = lf; mod->name = modname; TAILQ_INSERT_TAIL(&found_modules, mod, link); } } return error; }