diff options
Diffstat (limited to 'sys/kern/kern_linker.c')
| -rw-r--r-- | sys/kern/kern_linker.c | 1379 |
1 files changed, 1379 insertions, 0 deletions
diff --git a/sys/kern/kern_linker.c b/sys/kern/kern_linker.c new file mode 100644 index 0000000..f81e000 --- /dev/null +++ b/sys/kern/kern_linker.c @@ -0,0 +1,1379 @@ +/*- + * 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. + * + * $FreeBSD$ + */ + +#include "opt_ddb.h" + +#include <sys/param.h> +#include <sys/kernel.h> +#include <sys/systm.h> +#include <sys/malloc.h> +#include <sys/sysproto.h> +#include <sys/sysent.h> +#include <sys/proc.h> +#include <sys/lock.h> +#include <sys/module.h> +#include <sys/linker.h> +#include <sys/fcntl.h> +#include <sys/libkern.h> +#include <sys/namei.h> +#include <sys/vnode.h> +#include <sys/sysctl.h> + + +#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); +} + +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); + 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); + if (newdeps == NULL) + return ENOMEM; + bzero(newdeps, (file->ndeps + 1) * sizeof(linker_file_t*)); + + 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); + if (!cp) { + KLD_DPF(SYM, ("linker_file_lookup_symbol: nomem\n")); + return 0; + } + bzero(cp, sizeof(struct common_symbol) + common_size + strlen(name)+ 1); + + 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; + 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; + int i; + 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); + if (mod == NULL) + panic("no memory for module list"); + bzero(mod, sizeof(*mod)); + 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); + 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); + if (mod == NULL) + panic("no memory for module list"); + bzero(mod, sizeof(*mod)); + 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 linker_path[MAXPATHLEN] = "/;/boot/;/modules/"; + +SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path, + sizeof(linker_path), "module load search 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; + 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), 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), 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); + error = vn_open(&nd, FREAD, 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); + if (mod == NULL) + panic("no memory for module list"); + bzero(mod, sizeof(*mod)); + mod->container = lf; + mod->name = modname; + TAILQ_INSERT_TAIL(&found_modules, mod, link); + } + } + return error; +} |
