imgact_gzip.c revision 139804
13332Sphk/*- 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 * ---------------------------------------------------------------------------- 83332Sphk */ 93332Sphk 103332Sphk/* 113784Sphk * This module handles execution of a.out files which have been run through 123332Sphk * "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... 203417Scsgr * so is the rest... 213332Sphk * tidy up unnecesary includes 223332Sphk */ 23116182Sobrien 24116182Sobrien#include <sys/cdefs.h> 25116182Sobrien__FBSDID("$FreeBSD: head/sys/kern/imgact_gzip.c 139804 2005-01-06 23:35:40Z imp $"); 263784Sphk 273332Sphk#include <sys/param.h> 283332Sphk#include <sys/exec.h> 293332Sphk#include <sys/imgact.h> 303332Sphk#include <sys/imgact_aout.h> 3176166Smarkm#include <sys/kernel.h> 323507Scsgr#include <sys/lock.h> 3376166Smarkm#include <sys/mman.h> 3415494Sbde#include <sys/mutex.h> 353507Scsgr#include <sys/proc.h> 363332Sphk#include <sys/resourcevar.h> 373507Scsgr#include <sys/sysent.h> 3815494Sbde#include <sys/systm.h> 393784Sphk#include <sys/vnode.h> 403332Sphk#include <sys/inflate.h> 413332Sphk 4212662Sdg#include <vm/vm.h> 4312662Sdg#include <vm/vm_param.h> 4412662Sdg#include <vm/pmap.h> 453332Sphk#include <vm/vm_map.h> 4612662Sdg#include <vm/vm_kern.h> 473332Sphk#include <vm/vm_extern.h> 483784Sphk 493784Sphkstruct imgact_gzip { 503784Sphk struct image_params *ip; 513784Sphk struct exec a_out; 5248079Shoek int error; 533784Sphk int gotheader; 543784Sphk int where; 553784Sphk u_char *inbuf; 563784Sphk u_long offset; 573784Sphk u_long output; 583784Sphk u_long len; 593784Sphk int idx; 603784Sphk u_long virtual_offset, file_offset, file_end, bss_size; 613784Sphk}; 6292723Salfred 6392723Salfredstatic int exec_gzip_imgact(struct image_params *imgp); 6492723Salfredstatic int NextByte(void *vp); 6592723Salfredstatic int do_aout_hdr(struct imgact_gzip *); 663784Sphkstatic int Flush(void *vp, u_char *, u_long siz); 6712568Sbde 6812130Sdgstatic int 6912130Sdgexec_gzip_imgact(imgp) 703332Sphk struct image_params *imgp; 713784Sphk{ 7217974Sbde int error, error2 = 0; 733784Sphk const u_char *p = (const u_char *) imgp->image_header; 743784Sphk struct imgact_gzip igz; 7517386Sphk struct inflate infl; 763332Sphk struct vmspace *vmspace; 773348Sphk 783784Sphk /* If these four are not OK, it isn't a gzip file */ 793784Sphk if (p[0] != 0x1f) 803784Sphk return -1; /* 0 Simply magic */ 813784Sphk if (p[1] != 0x8b) 823784Sphk return -1; /* 1 Simply magic */ 833784Sphk if (p[2] != 0x08) 843784Sphk return -1; /* 2 Compression method */ 853784Sphk if (p[9] != 0x03) 863332Sphk return -1; /* 9 OS compressed on */ 873784Sphk 883784Sphk /* 893784Sphk * If this one contains anything but a comment or a filename marker, 903348Sphk * we don't want to chew on it 913784Sphk */ 923784Sphk if (p[3] & ~(0x18)) 933332Sphk return ENOEXEC; /* 3 Flags */ 943348Sphk 953784Sphk /* These are of no use to us */ 963784Sphk /* 4-7 Timestamp */ 973348Sphk /* 8 Extra flags */ 983784Sphk 993784Sphk bzero(&igz, sizeof igz); 1003784Sphk bzero(&infl, sizeof infl); 1013784Sphk infl.gz_private = (void *) &igz; 1023784Sphk infl.gz_input = NextByte; 1033332Sphk infl.gz_output = Flush; 10412130Sdg 1053784Sphk igz.ip = imgp; 1063353Sphk igz.idx = 10; 1073784Sphk 1083784Sphk if (p[3] & 0x08) { /* skip a filename */ 1093784Sphk while (p[igz.idx++]) 1103784Sphk if (igz.idx >= PAGE_SIZE) 1113348Sphk return ENOEXEC; 1123784Sphk } 1133784Sphk if (p[3] & 0x10) { /* skip a comment */ 1143784Sphk while (p[igz.idx++]) 1153784Sphk if (igz.idx >= PAGE_SIZE) 1163348Sphk return ENOEXEC; 11717386Sphk } 1183332Sphk igz.len = imgp->attr->va_size; 1193784Sphk 1203348Sphk error = inflate(&infl); 12148079Shoek 12248079Shoek /* 12348079Shoek * The unzipped file may not even have been long enough to contain 12448079Shoek * a header giving Flush() a chance to return error. Check for this. 12548079Shoek */ 12648079Shoek if ( !igz.gotheader ) 12748079Shoek return ENOEXEC; 12817386Sphk 12917386Sphk if ( !error ) { 13017386Sphk vmspace = imgp->proc->p_vmspace; 13117386Sphk error = vm_map_protect(&vmspace->vm_map, 13217386Sphk (vm_offset_t) vmspace->vm_taddr, 13317386Sphk (vm_offset_t) (vmspace->vm_taddr + 13417386Sphk (vmspace->vm_tsize << PAGE_SHIFT)) , 13517386Sphk VM_PROT_READ|VM_PROT_EXECUTE,0); 13617386Sphk } 1373784Sphk 1383784Sphk if (igz.inbuf) { 1396579Sdg error2 = 1406579Sdg vm_map_remove(kernel_map, (vm_offset_t) igz.inbuf, 1413332Sphk (vm_offset_t) igz.inbuf + PAGE_SIZE); 1423784Sphk } 1433784Sphk if (igz.error || error || error2) { 1443784Sphk printf("Output=%lu ", igz.output); 1453784Sphk printf("Inflate_error=%d igz.error=%d error2=%d where=%d\n", 1463348Sphk error, igz.error, error2, igz.where); 1473784Sphk } 1483784Sphk if (igz.error) 1493784Sphk return igz.error; 1503784Sphk if (error) 1518876Srgrimes return ENOEXEC; 1523784Sphk if (error2) 1533784Sphk return error2; 1543332Sphk return 0; 1553332Sphk} 1563784Sphk 1573784Sphkstatic int 1583332Sphkdo_aout_hdr(struct imgact_gzip * gz) 1593784Sphk{ 16024848Sdyson int error; 16114703Sbde struct vmspace *vmspace; 1623332Sphk vm_offset_t vmaddr; 1633784Sphk 1643784Sphk /* 1653784Sphk * Set file/virtual offset based on a.out variant. We do two cases: 1663784Sphk * host byte order and network byte order (for NetBSD compatibility) 1673784Sphk */ 1683332Sphk switch ((int) (gz->a_out.a_magic & 0xffff)) { 1693784Sphk case ZMAGIC: 1703784Sphk gz->virtual_offset = 0; 17115538Sphk if (gz->a_out.a_text) { 1723784Sphk gz->file_offset = PAGE_SIZE; 1733784Sphk } else { 1743784Sphk /* Bill's "screwball mode" */ 1753784Sphk gz->file_offset = 0; 1763784Sphk } 1773332Sphk break; 17815538Sphk case QMAGIC: 1793784Sphk gz->virtual_offset = PAGE_SIZE; 1803784Sphk gz->file_offset = 0; 1813332Sphk break; 1823784Sphk default: 1833784Sphk /* NetBSD compatibility */ 1843784Sphk switch ((int) (ntohl(gz->a_out.a_magic) & 0xffff)) { 1853784Sphk case ZMAGIC: 18615538Sphk case QMAGIC: 1873784Sphk gz->virtual_offset = PAGE_SIZE; 1883784Sphk gz->file_offset = 0; 1893784Sphk break; 1903784Sphk default: 1913784Sphk gz->where = __LINE__; 1923784Sphk return (-1); 1933332Sphk } 1943332Sphk } 19515538Sphk 1963332Sphk gz->bss_size = roundup(gz->a_out.a_bss, PAGE_SIZE); 1973784Sphk 1983784Sphk /* 1993784Sphk * Check various fields in header for validity/bounds. 2003784Sphk */ 2013784Sphk if ( /* entry point must lay with text region */ 2023784Sphk gz->a_out.a_entry < gz->virtual_offset || 2033332Sphk gz->a_out.a_entry >= gz->virtual_offset + gz->a_out.a_text || 2043332Sphk 20515538Sphk /* text and data size must each be page rounded */ 2063784Sphk gz->a_out.a_text & PAGE_MASK || gz->a_out.a_data & PAGE_MASK) { 2073784Sphk gz->where = __LINE__; 2083784Sphk return (-1); 2093784Sphk } 2103784Sphk /* 2113784Sphk * text/data/bss must not exceed limits 212125454Sjhb */ 2133784Sphk PROC_LOCK(gz->ip->proc); 21484783Sps if ( /* text can't exceed maximum text size */ 2153332Sphk gz->a_out.a_text > maxtsiz || 2163332Sphk 2173784Sphk /* data + bss can't exceed rlimit */ 218125454Sjhb gz->a_out.a_data + gz->bss_size > 219125454Sjhb lim_cur(gz->ip->proc, RLIMIT_DATA)) { 2203784Sphk PROC_UNLOCK(gz->ip->proc); 2213784Sphk gz->where = __LINE__; 2223784Sphk return (ENOMEM); 223125454Sjhb } 2243784Sphk PROC_UNLOCK(gz->ip->proc); 2253784Sphk /* Find out how far we should go */ 2263332Sphk gz->file_end = gz->file_offset + gz->a_out.a_text + gz->a_out.a_data; 2273784Sphk 2283784Sphk /* copy in arguments and/or environment from old process */ 2293784Sphk error = exec_extract_strings(gz->ip); 2303784Sphk if (error) { 2313784Sphk gz->where = __LINE__; 2323784Sphk return (error); 2333784Sphk } 2343784Sphk /* 2353784Sphk * Destroy old process VM and create a new one (with a new stack) 236103767Sjake */ 2373348Sphk exec_new_vmspace(gz->ip, &aout_sysvec); 23824848Sdyson 23924848Sdyson vmspace = gz->ip->proc->p_vmspace; 2403784Sphk 2413332Sphk vmaddr = gz->virtual_offset; 2423784Sphk 2433784Sphk error = vm_mmap(&vmspace->vm_map, 24417386Sphk &vmaddr, 24517386Sphk gz->a_out.a_text + gz->a_out.a_data, 2463784Sphk VM_PROT_ALL, VM_PROT_ALL, MAP_ANON | MAP_FIXED, 2473784Sphk 0, 2483332Sphk 0); 2493784Sphk 2503784Sphk if (error) { 2513784Sphk gz->where = __LINE__; 2523784Sphk return (error); 25317386Sphk } 2546579Sdg 2556579Sdg if (gz->bss_size != 0) { 25614087Sphk /* 25714087Sphk * Allocate demand-zeroed area for uninitialized data. 25814087Sphk * "bss" = 'block started by symbol' - named after the 2596579Sdg * IBM 7090 instruction of the same name. 26014087Sphk */ 26114087Sphk vmaddr = gz->virtual_offset + gz->a_out.a_text + 26217386Sphk gz->a_out.a_data; 26317386Sphk error = vm_map_find(&vmspace->vm_map, 26417386Sphk NULL, 26517386Sphk 0, 26617386Sphk &vmaddr, 26717386Sphk gz->bss_size, 2686579Sdg FALSE, VM_PROT_ALL, VM_PROT_ALL, 0); 2696579Sdg if (error) { 2706579Sdg gz->where = __LINE__; 2716579Sdg return (error); 2723784Sphk } 2733784Sphk } 2743784Sphk /* Fill in process VM information */ 2753784Sphk vmspace->vm_tsize = gz->a_out.a_text >> PAGE_SHIFT; 27637656Sbde vmspace->vm_dsize = (gz->a_out.a_data + gz->bss_size) >> PAGE_SHIFT; 27737656Sbde vmspace->vm_taddr = (caddr_t) (uintptr_t) gz->virtual_offset; 27837656Sbde vmspace->vm_daddr = (caddr_t) (uintptr_t) 2793332Sphk (gz->virtual_offset + gz->a_out.a_text); 2803784Sphk 2813784Sphk /* Fill in image_params */ 2823784Sphk gz->ip->interpreted = 0; 2833332Sphk gz->ip->entry_addr = gz->a_out.a_entry; 2843784Sphk 2853332Sphk gz->ip->proc->p_sysent = &aout_sysvec; 2863784Sphk 2873784Sphk return 0; 2883332Sphk} 2893784Sphk 2903784Sphkstatic int 2913784SphkNextByte(void *vp) 2923784Sphk{ 2933784Sphk int error; 2943332Sphk struct imgact_gzip *igz = (struct imgact_gzip *) vp; 2953784Sphk 2963784Sphk if (igz->idx >= igz->len) { 2973784Sphk igz->where = __LINE__; 2983784Sphk return GZ_EOF; 2993784Sphk } 3003784Sphk if (igz->inbuf && igz->idx < (igz->offset + PAGE_SIZE)) { 3013784Sphk return igz->inbuf[(igz->idx++) - igz->offset]; 3023784Sphk } 3036579Sdg if (igz->inbuf) { 3046579Sdg error = vm_map_remove(kernel_map, (vm_offset_t) igz->inbuf, 3053784Sphk (vm_offset_t) igz->inbuf + PAGE_SIZE); 3063784Sphk if (error) { 3073784Sphk igz->where = __LINE__; 3083784Sphk igz->error = error; 3093784Sphk return GZ_EOF; 3103784Sphk } 3116342Sphk } 3123332Sphk igz->offset = igz->idx & ~PAGE_MASK; 3133784Sphk 3143784Sphk error = vm_mmap(kernel_map, /* map */ 3153784Sphk (vm_offset_t *) & igz->inbuf, /* address */ 3163784Sphk PAGE_SIZE, /* size */ 3173784Sphk VM_PROT_READ, /* protection */ 3183784Sphk VM_PROT_READ, /* max protection */ 31912130Sdg 0, /* flags */ 3203784Sphk (caddr_t) 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]; 3283332Sphk} 3293784Sphk 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; 3353348Sphk int i; 336108533Sschweikh 3373784Sphk /* 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; 34548079Shoek if (gz->output == sizeof gz->a_out) { 3463784Sphk gz->gotheader = 1; 3473784Sphk i = do_aout_hdr(gz); 3483785Sphk if (i == -1) { 3493785Sphk if (!gz->where) 3503784Sphk 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; 35731718Sjdp } 35837656Sbde if (gz->file_offset == 0) { 35937015Sbde q = (u_char *) (uintptr_t) gz->virtual_offset; 3603784Sphk copyout(&gz->a_out, q, sizeof gz->a_out); 3613784Sphk } 3623784Sphk } 3633784Sphk } 36437015Sbde /* Skip over zero-padded first PAGE if needed */ 36537015Sbde if (gz->output < gz->file_offset && 3663784Sphk 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) { 37337656Sbde i = min(siz, gz->file_end - gz->output); 37437656Sbde q = (u_char *) (uintptr_t) 37537015Sbde (gz->virtual_offset + gz->output - gz->file_offset); 3763784Sphk copyout(p, q, i); 3773784Sphk gz->output += i; 3783784Sphk p += i; 3793784Sphk siz -= i; 3803784Sphk } 3813784Sphk gz->output += siz; 3823332Sphk return 0; 3833332Sphk} 3843784Sphk 3853332Sphk 3863332Sphk/* 3873332Sphk * Tell kern_execve.c about it, with a little help from the linker. 38843402Sdillon */ 38940435Speterstatic struct execsw gzip_execsw = {exec_gzip_imgact, "gzip"}; 390EXEC_SET(execgzip, gzip_execsw); 391