1139804Simp/*- 23332Sphk * ---------------------------------------------------------------------------- 33332Sphk * "THE BEER-WARE LICENSE" (Revision 42): 493149Sphk * <phk@FreeBSD.org> wrote this file. As long as you retain this notice you 53332Sphk * can do whatever you want with this stuff. If we meet some day, and you think 63332Sphk * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp 73332Sphk * ---------------------------------------------------------------------------- 8139804Simp */ 9139804Simp 10139804Simp/* 113332Sphk * This module handles execution of a.out files which have been run through 123784Sphk * "gzip". This saves diskspace, but wastes cpu-cycles and VM. 133332Sphk * 143332Sphk * TODO: 153332Sphk * text-segments should be made R/O after being filled 163332Sphk * is the vm-stuff safe ? 173332Sphk * should handle the entire header of gzip'ed stuff. 183332Sphk * inflate isn't quite reentrant yet... 193332Sphk * error-handling is a mess... 203332Sphk * so is the rest... 21249583Sgabor * tidy up unnecessary includes 223332Sphk */ 233332Sphk 24116182Sobrien#include <sys/cdefs.h> 25116182Sobrien__FBSDID("$FreeBSD: releng/10.3/sys/kern/imgact_gzip.c 255426 2013-09-09 18:11:59Z jhb $"); 26116182Sobrien 273784Sphk#include <sys/param.h> 283332Sphk#include <sys/exec.h> 293332Sphk#include <sys/imgact.h> 303332Sphk#include <sys/imgact_aout.h> 313332Sphk#include <sys/kernel.h> 3276166Smarkm#include <sys/lock.h> 333507Scsgr#include <sys/mman.h> 3476166Smarkm#include <sys/mutex.h> 3515494Sbde#include <sys/proc.h> 36220373Strasz#include <sys/racct.h> 373507Scsgr#include <sys/resourcevar.h> 383332Sphk#include <sys/sysent.h> 393507Scsgr#include <sys/systm.h> 4015494Sbde#include <sys/vnode.h> 413784Sphk#include <sys/inflate.h> 423332Sphk 433332Sphk#include <vm/vm.h> 4412662Sdg#include <vm/vm_param.h> 4512662Sdg#include <vm/pmap.h> 4612662Sdg#include <vm/vm_map.h> 473332Sphk#include <vm/vm_kern.h> 4812662Sdg#include <vm/vm_extern.h> 493332Sphk 503784Sphkstruct imgact_gzip { 513784Sphk struct image_params *ip; 523784Sphk struct exec a_out; 533784Sphk int error; 5448079Shoek int gotheader; 553784Sphk int where; 563784Sphk u_char *inbuf; 573784Sphk u_long offset; 583784Sphk u_long output; 593784Sphk u_long len; 603784Sphk int idx; 613784Sphk u_long virtual_offset, file_offset, file_end, bss_size; 623784Sphk}; 633784Sphk 6492723Salfredstatic int exec_gzip_imgact(struct image_params *imgp); 6592723Salfredstatic int NextByte(void *vp); 6692723Salfredstatic int do_aout_hdr(struct imgact_gzip *); 6792723Salfredstatic int Flush(void *vp, u_char *, u_long siz); 683784Sphk 6912568Sbdestatic int 7012130Sdgexec_gzip_imgact(imgp) 7112130Sdg struct image_params *imgp; 723332Sphk{ 73231885Skib int error; 7417974Sbde const u_char *p = (const u_char *) imgp->image_header; 753784Sphk struct imgact_gzip igz; 763784Sphk struct inflate infl; 7717386Sphk struct vmspace *vmspace; 783332Sphk 793348Sphk /* If these four are not OK, it isn't a gzip file */ 803784Sphk if (p[0] != 0x1f) 813784Sphk return -1; /* 0 Simply magic */ 823784Sphk if (p[1] != 0x8b) 833784Sphk return -1; /* 1 Simply magic */ 843784Sphk if (p[2] != 0x08) 853784Sphk return -1; /* 2 Compression method */ 863784Sphk if (p[9] != 0x03) 873784Sphk return -1; /* 9 OS compressed on */ 883332Sphk 893784Sphk /* 903784Sphk * If this one contains anything but a comment or a filename marker, 913784Sphk * we don't want to chew on it 923348Sphk */ 933784Sphk if (p[3] & ~(0x18)) 943784Sphk return ENOEXEC; /* 3 Flags */ 953332Sphk 963348Sphk /* These are of no use to us */ 973784Sphk /* 4-7 Timestamp */ 983784Sphk /* 8 Extra flags */ 993348Sphk 1003784Sphk bzero(&igz, sizeof igz); 1013784Sphk bzero(&infl, sizeof infl); 1023784Sphk infl.gz_private = (void *) &igz; 1033784Sphk infl.gz_input = NextByte; 1043784Sphk infl.gz_output = Flush; 1053332Sphk 10612130Sdg igz.ip = imgp; 1073784Sphk igz.idx = 10; 1083353Sphk 1093784Sphk if (p[3] & 0x08) { /* skip a filename */ 1103784Sphk while (p[igz.idx++]) 1113784Sphk if (igz.idx >= PAGE_SIZE) 1123784Sphk return ENOEXEC; 1133348Sphk } 1143784Sphk if (p[3] & 0x10) { /* skip a comment */ 1153784Sphk while (p[igz.idx++]) 1163784Sphk if (igz.idx >= PAGE_SIZE) 1173784Sphk return ENOEXEC; 1183348Sphk } 11917386Sphk igz.len = imgp->attr->va_size; 1203332Sphk 1213784Sphk error = inflate(&infl); 1223348Sphk 12348079Shoek /* 12448079Shoek * The unzipped file may not even have been long enough to contain 12548079Shoek * a header giving Flush() a chance to return error. Check for this. 12648079Shoek */ 12748079Shoek if ( !igz.gotheader ) 12848079Shoek return ENOEXEC; 12948079Shoek 13017386Sphk if ( !error ) { 13117386Sphk vmspace = imgp->proc->p_vmspace; 13217386Sphk error = vm_map_protect(&vmspace->vm_map, 13317386Sphk (vm_offset_t) vmspace->vm_taddr, 13417386Sphk (vm_offset_t) (vmspace->vm_taddr + 13517386Sphk (vmspace->vm_tsize << PAGE_SHIFT)) , 13617386Sphk VM_PROT_READ|VM_PROT_EXECUTE,0); 13717386Sphk } 13817386Sphk 139231885Skib if (igz.inbuf) 140254025Sjeff kmap_free_wakeup(exec_map, (vm_offset_t)igz.inbuf, PAGE_SIZE); 141231885Skib if (igz.error || error) { 1423784Sphk printf("Output=%lu ", igz.output); 143231885Skib printf("Inflate_error=%d igz.error=%d where=%d\n", 144231885Skib error, igz.error, igz.where); 1453348Sphk } 1463784Sphk if (igz.error) 1473784Sphk return igz.error; 1483784Sphk if (error) 1493784Sphk return ENOEXEC; 1503784Sphk return 0; 1513332Sphk} 1523332Sphk 1533784Sphkstatic int 1543784Sphkdo_aout_hdr(struct imgact_gzip * gz) 1553332Sphk{ 1563784Sphk int error; 15724848Sdyson struct vmspace *vmspace; 15814703Sbde vm_offset_t vmaddr; 1593332Sphk 1603784Sphk /* 1613784Sphk * Set file/virtual offset based on a.out variant. We do two cases: 1623784Sphk * host byte order and network byte order (for NetBSD compatibility) 1633784Sphk */ 164237694Simp switch ((int) (gz->a_out.a_midmag & 0xffff)) { 1653332Sphk case ZMAGIC: 1663784Sphk gz->virtual_offset = 0; 1673784Sphk if (gz->a_out.a_text) { 16815538Sphk gz->file_offset = PAGE_SIZE; 1693784Sphk } else { 1703784Sphk /* Bill's "screwball mode" */ 1713784Sphk gz->file_offset = 0; 1723784Sphk } 1733784Sphk break; 1743332Sphk case QMAGIC: 17515538Sphk gz->virtual_offset = PAGE_SIZE; 1763784Sphk gz->file_offset = 0; 1773784Sphk break; 1783332Sphk default: 1793784Sphk /* NetBSD compatibility */ 180237694Simp switch ((int) (ntohl(gz->a_out.a_midmag) & 0xffff)) { 1813784Sphk case ZMAGIC: 1823784Sphk case QMAGIC: 18315538Sphk gz->virtual_offset = PAGE_SIZE; 1843784Sphk gz->file_offset = 0; 1853784Sphk break; 1863784Sphk default: 1873784Sphk gz->where = __LINE__; 1883784Sphk return (-1); 1893784Sphk } 1903332Sphk } 1913332Sphk 19215538Sphk gz->bss_size = roundup(gz->a_out.a_bss, PAGE_SIZE); 1933332Sphk 1943784Sphk /* 1953784Sphk * Check various fields in header for validity/bounds. 1963784Sphk */ 1973784Sphk if ( /* entry point must lay with text region */ 1983784Sphk gz->a_out.a_entry < gz->virtual_offset || 1993784Sphk gz->a_out.a_entry >= gz->virtual_offset + gz->a_out.a_text || 2003332Sphk 2013332Sphk /* text and data size must each be page rounded */ 20215538Sphk gz->a_out.a_text & PAGE_MASK || gz->a_out.a_data & PAGE_MASK) { 2033784Sphk gz->where = __LINE__; 2043784Sphk return (-1); 2053784Sphk } 2063784Sphk /* 2073784Sphk * text/data/bss must not exceed limits 2083784Sphk */ 209125454Sjhb PROC_LOCK(gz->ip->proc); 2103784Sphk if ( /* text can't exceed maximum text size */ 21184783Sps gz->a_out.a_text > maxtsiz || 2123332Sphk 2133332Sphk /* data + bss can't exceed rlimit */ 2143784Sphk gz->a_out.a_data + gz->bss_size > 215220373Strasz lim_cur(gz->ip->proc, RLIMIT_DATA) || 216220373Strasz racct_set(gz->ip->proc, RACCT_DATA, 217220373Strasz gz->a_out.a_data + gz->bss_size) != 0) { 218125454Sjhb PROC_UNLOCK(gz->ip->proc); 2193784Sphk gz->where = __LINE__; 2203784Sphk return (ENOMEM); 2213784Sphk } 222125454Sjhb PROC_UNLOCK(gz->ip->proc); 2233784Sphk /* Find out how far we should go */ 2243784Sphk gz->file_end = gz->file_offset + gz->a_out.a_text + gz->a_out.a_data; 2253332Sphk 2263784Sphk /* 227153698Salc * Avoid a possible deadlock if the current address space is destroyed 228153698Salc * and that address space maps the locked vnode. In the common case, 229153698Salc * the locked vnode's v_usecount is decremented but remains greater 230153698Salc * than zero. Consequently, the vnode lock is not needed by vrele(). 231153698Salc * However, in cases where the vnode lock is external, such as nullfs, 232153698Salc * v_usecount may become zero. 233153698Salc */ 234175294Sattilio VOP_UNLOCK(gz->ip->vp, 0); 235153698Salc 236153698Salc /* 2373784Sphk * Destroy old process VM and create a new one (with a new stack) 2383784Sphk */ 239173361Skib error = exec_new_vmspace(gz->ip, &aout_sysvec); 2403348Sphk 241175202Sattilio vn_lock(gz->ip->vp, LK_EXCLUSIVE | LK_RETRY); 242173361Skib if (error) { 243173361Skib gz->where = __LINE__; 244173361Skib return (error); 245173361Skib } 246153698Salc 24724848Sdyson vmspace = gz->ip->proc->p_vmspace; 24824848Sdyson 2493784Sphk vmaddr = gz->virtual_offset; 2503332Sphk 2513784Sphk error = vm_mmap(&vmspace->vm_map, 2523784Sphk &vmaddr, 25317386Sphk gz->a_out.a_text + gz->a_out.a_data, 25417386Sphk VM_PROT_ALL, VM_PROT_ALL, MAP_ANON | MAP_FIXED, 255144501Sjhb OBJT_DEFAULT, 256144501Sjhb NULL, 2573784Sphk 0); 2583332Sphk 2593784Sphk if (error) { 2603784Sphk gz->where = __LINE__; 2613784Sphk return (error); 2623784Sphk } 26317386Sphk 2646579Sdg if (gz->bss_size != 0) { 2656579Sdg /* 26614087Sphk * Allocate demand-zeroed area for uninitialized data. 26714087Sphk * "bss" = 'block started by symbol' - named after the 26814087Sphk * IBM 7090 instruction of the same name. 2696579Sdg */ 27014087Sphk vmaddr = gz->virtual_offset + gz->a_out.a_text + 27114087Sphk gz->a_out.a_data; 272255426Sjhb error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr, 273255426Sjhb gz->bss_size, 0, VMFS_NO_SPACE, VM_PROT_ALL, VM_PROT_ALL, 274255426Sjhb 0); 2756579Sdg if (error) { 2766579Sdg gz->where = __LINE__; 2776579Sdg return (error); 2786579Sdg } 2793784Sphk } 2803784Sphk /* Fill in process VM information */ 2813784Sphk vmspace->vm_tsize = gz->a_out.a_text >> PAGE_SHIFT; 2823784Sphk vmspace->vm_dsize = (gz->a_out.a_data + gz->bss_size) >> PAGE_SHIFT; 28337656Sbde vmspace->vm_taddr = (caddr_t) (uintptr_t) gz->virtual_offset; 28437656Sbde vmspace->vm_daddr = (caddr_t) (uintptr_t) 28537656Sbde (gz->virtual_offset + gz->a_out.a_text); 2863332Sphk 2873784Sphk /* Fill in image_params */ 2883784Sphk gz->ip->interpreted = 0; 2893784Sphk gz->ip->entry_addr = gz->a_out.a_entry; 2903332Sphk 2913784Sphk gz->ip->proc->p_sysent = &aout_sysvec; 2923332Sphk 2933784Sphk return 0; 2943784Sphk} 2953332Sphk 2963784Sphkstatic int 2973784SphkNextByte(void *vp) 2983784Sphk{ 2993784Sphk int error; 3003784Sphk struct imgact_gzip *igz = (struct imgact_gzip *) vp; 3013332Sphk 3023784Sphk if (igz->idx >= igz->len) { 3033784Sphk igz->where = __LINE__; 3043784Sphk return GZ_EOF; 3053784Sphk } 3063784Sphk if (igz->inbuf && igz->idx < (igz->offset + PAGE_SIZE)) { 3073784Sphk return igz->inbuf[(igz->idx++) - igz->offset]; 3083784Sphk } 309231885Skib if (igz->inbuf) 310254025Sjeff kmap_free_wakeup(exec_map, (vm_offset_t)igz->inbuf, PAGE_SIZE); 3116342Sphk igz->offset = igz->idx & ~PAGE_MASK; 3123332Sphk 313231885Skib error = vm_mmap(exec_map, /* map */ 3143784Sphk (vm_offset_t *) & igz->inbuf, /* address */ 3153784Sphk PAGE_SIZE, /* size */ 3163784Sphk VM_PROT_READ, /* protection */ 3173784Sphk VM_PROT_READ, /* max protection */ 3183784Sphk 0, /* flags */ 319144501Sjhb OBJT_VNODE, /* handle type */ 320144501Sjhb igz->ip->vp, /* vnode */ 3213784Sphk igz->offset); /* offset */ 3223784Sphk if (error) { 3233784Sphk igz->where = __LINE__; 3243784Sphk igz->error = error; 3253784Sphk return GZ_EOF; 3263784Sphk } 3273784Sphk return igz->inbuf[(igz->idx++) - igz->offset]; 3283784Sphk} 3293332Sphk 3303784Sphkstatic int 3313784SphkFlush(void *vp, u_char * ptr, u_long siz) 3323784Sphk{ 3333784Sphk struct imgact_gzip *gz = (struct imgact_gzip *) vp; 3343784Sphk u_char *p = ptr, *q; 3353784Sphk int i; 3363348Sphk 337108533Sschweikh /* First, find an a.out-header. */ 3383784Sphk if (gz->output < sizeof gz->a_out) { 3393784Sphk q = (u_char *) & gz->a_out; 3403784Sphk i = min(siz, sizeof gz->a_out - gz->output); 3413784Sphk bcopy(p, q + gz->output, i); 3423784Sphk gz->output += i; 3433784Sphk p += i; 3443784Sphk siz -= i; 3453784Sphk if (gz->output == sizeof gz->a_out) { 34648079Shoek gz->gotheader = 1; 3473784Sphk i = do_aout_hdr(gz); 3483784Sphk if (i == -1) { 3493785Sphk if (!gz->where) 3503785Sphk gz->where = __LINE__; 3513784Sphk gz->error = ENOEXEC; 3523784Sphk return ENOEXEC; 3533784Sphk } else if (i) { 3543784Sphk gz->where = __LINE__; 3553784Sphk gz->error = i; 3563784Sphk return ENOEXEC; 3573784Sphk } 35831718Sjdp if (gz->file_offset == 0) { 35937656Sbde q = (u_char *) (uintptr_t) gz->virtual_offset; 36037015Sbde copyout(&gz->a_out, q, sizeof gz->a_out); 3613784Sphk } 3623784Sphk } 3633784Sphk } 3643784Sphk /* Skip over zero-padded first PAGE if needed */ 36537015Sbde if (gz->output < gz->file_offset && 36637015Sbde gz->output + siz > gz->file_offset) { 3673784Sphk i = min(siz, gz->file_offset - gz->output); 3683784Sphk gz->output += i; 3693784Sphk p += i; 3703784Sphk siz -= i; 3713784Sphk } 3723784Sphk if (gz->output >= gz->file_offset && gz->output < gz->file_end) { 3733784Sphk i = min(siz, gz->file_end - gz->output); 37437656Sbde q = (u_char *) (uintptr_t) 37537656Sbde (gz->virtual_offset + gz->output - gz->file_offset); 37637015Sbde copyout(p, q, i); 3773784Sphk gz->output += i; 3783784Sphk p += i; 3793784Sphk siz -= i; 3803784Sphk } 3813784Sphk gz->output += siz; 3823784Sphk return 0; 3833332Sphk} 3843332Sphk 3853784Sphk 3863332Sphk/* 3873332Sphk * Tell kern_execve.c about it, with a little help from the linker. 3883332Sphk */ 38943402Sdillonstatic struct execsw gzip_execsw = {exec_gzip_imgact, "gzip"}; 39040435SpeterEXEC_SET(execgzip, gzip_execsw); 391