rpm 5.2.1

rpmdb/legacy.c

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00001 
00005 #include "system.h"
00006 
00007 #if defined(HAVE_GELF_H)
00008 #if LIBELF_H_LFS_CONFLICT
00009 /* some gelf.h/libelf.h implementations (Solaris) are
00010  * incompatible with the Large File API
00011  */
00012 # undef _LARGEFILE64_SOURCE
00013 # undef _LARGEFILE_SOURCE
00014 # undef _FILE_OFFSET_BITS
00015 # define _FILE_OFFSET_BITS 32
00016 #endif
00017 #if defined(__LCLINT__)
00018 /*@-incondefs@*/
00019 typedef long long loff_t;
00020 /*@=incondefs@*/
00021 #endif
00022 #include <gelf.h>
00023 
00024 #if !defined(DT_GNU_PRELINKED)
00025 #define DT_GNU_PRELINKED        0x6ffffdf5
00026 #endif
00027 #if !defined(DT_GNU_LIBLIST)
00028 #define DT_GNU_LIBLIST          0x6ffffef9
00029 #endif
00030 
00031 #endif
00032 
00033 #include "rpmio_internal.h"
00034 #include <rpmmacro.h>
00035 #include "misc.h"
00036 #include "legacy.h"
00037 #include "debug.h"
00038 
00039 #define alloca_strdup(_s)       strcpy(alloca(strlen(_s)+1), (_s))
00040 
00048 /*@-compdef -moduncon -noeffectuncon @*/
00049 static int open_dso(const char * path, /*@null@*/ pid_t * pidp, /*@null@*/ size_t *fsizep)
00050         /*@globals rpmGlobalMacroContext, h_errno, fileSystem, internalState @*/
00051         /*@modifies *pidp, *fsizep, rpmGlobalMacroContext,
00052                 fileSystem, internalState @*/
00053 {
00054 /*@only@*/
00055     static const char * cmd = NULL;
00056     static int oneshot = 0;
00057     int fdno;
00058 
00059     if (!oneshot) {
00060         cmd = rpmExpand("%{?__prelink_undo_cmd}", NULL);
00061         oneshot++;
00062     }
00063 
00064     if (pidp) *pidp = 0;
00065 
00066     if (fsizep) {
00067         struct stat sb, * st = &sb;
00068         if (stat(path, st) < 0)
00069             return -1;
00070         *fsizep = (size_t)st->st_size;
00071     }
00072 
00073     fdno = open(path, O_RDONLY);
00074     if (fdno < 0)
00075         return fdno;
00076 
00077     if (!(cmd && *cmd))
00078         return fdno;
00079 
00080 #if defined(HAVE_GELF_H) && defined(HAVE_LIBELF)
00081  {  Elf *elf = NULL;
00082     Elf_Scn *scn = NULL;
00083     Elf_Data *data = NULL;
00084     GElf_Ehdr ehdr;
00085     GElf_Shdr shdr;
00086     GElf_Dyn dyn;
00087     int bingo;
00088 
00089     (void) elf_version(EV_CURRENT);
00090 
00091 /*@-evalorder@*/
00092     if ((elf = elf_begin (fdno, ELF_C_READ, NULL)) == NULL
00093      || elf_kind(elf) != ELF_K_ELF
00094      || gelf_getehdr(elf, &ehdr) == NULL
00095      || !(ehdr.e_type == ET_DYN || ehdr.e_type == ET_EXEC))
00096         goto exit;
00097 /*@=evalorder@*/
00098 
00099     bingo = 0;
00100     while (!bingo && (scn = elf_nextscn(elf, scn)) != NULL) {
00101         (void) gelf_getshdr(scn, &shdr);
00102         if (shdr.sh_type != SHT_DYNAMIC)
00103             continue;
00104         while (!bingo && (data = elf_getdata (scn, data)) != NULL) {
00105             unsigned maxndx = (unsigned) (data->d_size / shdr.sh_entsize);
00106             unsigned ndx;
00107 
00108             for (ndx = 0; ndx < maxndx; ++ndx) {
00109 /*@-uniondef@*/
00110                 (void) gelf_getdyn (data, ndx, &dyn);
00111 /*@=uniondef@*/
00112                 if (!(dyn.d_tag == DT_GNU_PRELINKED || dyn.d_tag == DT_GNU_LIBLIST))
00113                     /*@innercontinue@*/ continue;
00114                 bingo = 1;
00115                 /*@innerbreak@*/ break;
00116             }
00117         }
00118     }
00119 
00120     if (pidp != NULL && bingo) {
00121         int pipes[2];
00122         pid_t pid;
00123         int xx;
00124 
00125         xx = close(fdno);
00126         pipes[0] = pipes[1] = -1;
00127         xx = pipe(pipes);
00128         if (!(pid = fork())) {
00129             const char ** av;
00130             int ac;
00131             xx = close(pipes[0]);
00132             xx = dup2(pipes[1], STDOUT_FILENO);
00133             xx = close(pipes[1]);
00134             if (!poptParseArgvString(cmd, &ac, &av)) {
00135                 av[ac-1] = path;
00136                 av[ac] = NULL;
00137                 unsetenv("MALLOC_CHECK_");
00138                 xx = execve(av[0], (char *const *)av+1, environ);
00139             }
00140             _exit(127);
00141         }
00142         *pidp = pid;
00143         fdno = pipes[0];
00144         xx = close(pipes[1]);
00145     }
00146 
00147 exit:
00148     if (elf) (void) elf_end(elf);
00149  }
00150 #endif
00151 
00152     return fdno;
00153 }
00154 /*@=compdef =moduncon =noeffectuncon @*/
00155 
00156 int dodigest(int digestalgo, const char * fn, unsigned char * digest, int asAscii, size_t *fsizep)
00157 {
00158     const char * path;
00159     urltype ut = urlPath(fn, &path);
00160     unsigned char * dsum = NULL;
00161     size_t dlen;
00162     unsigned char buf[32*BUFSIZ];
00163     FD_t fd;
00164     size_t fsize = 0;
00165     pid_t pid = 0;
00166     int use_mmap;
00167     int rc = 0;
00168     int fdno;
00169 #if defined(HAVE_MMAP)
00170     int xx;
00171 #endif
00172 
00173 /*@-globs -internalglobs -mods @*/
00174     fdno = open_dso(path, &pid, &fsize);
00175 /*@=globs =internalglobs =mods @*/
00176     if (fdno < 0) {
00177         rc = 1;
00178         goto exit;
00179     }
00180 
00181     /* XXX 128 Mb resource cap for top(1) scrutiny, MADV_SEQUENTIAL better. */
00182     use_mmap = (pid == 0 && fsize <= 0x07ffffff);
00183 
00184     switch(ut) {
00185     case URL_IS_PATH:
00186     case URL_IS_UNKNOWN:
00187 #if defined(HAVE_MMAP)
00188       if (use_mmap) {
00189         DIGEST_CTX ctx;
00190         void * mapped = NULL;
00191 
00192         if (fsize) {
00193             mapped = mmap(NULL, fsize, PROT_READ, MAP_SHARED, fdno, 0);
00194             if (mapped == (void *)-1) {
00195                 xx = close(fdno);
00196                 rc = 1;
00197                 break;
00198             }
00199 
00200 #if defined(HAVE_MADVISE) && defined(MADV_SEQUENTIAL)
00201             xx = madvise(mapped, fsize, MADV_SEQUENTIAL);
00202 #endif
00203         }
00204 
00205         ctx = rpmDigestInit(digestalgo, RPMDIGEST_NONE);
00206         if (fsize)
00207             xx = rpmDigestUpdate(ctx, mapped, fsize);
00208         xx = rpmDigestFinal(ctx, &dsum, &dlen, asAscii);
00209         if (fsize)
00210             xx = munmap(mapped, fsize);
00211         xx = close(fdno);
00212         break;
00213       } /*@fallthrough@*/
00214 #endif
00215     case URL_IS_HTTPS:
00216     case URL_IS_HTTP:
00217     case URL_IS_FTP:
00218     case URL_IS_HKP:
00219     case URL_IS_DASH:
00220     default:
00221         /* Either use the pipe to prelink -y or open the URL. */
00222         fd = (pid != 0) ? fdDup(fdno) : Fopen(fn, "r.fdio");
00223         (void) close(fdno);
00224         if (fd == NULL || Ferror(fd)) {
00225             rc = 1;
00226             if (fd != NULL)
00227                 (void) Fclose(fd);
00228             break;
00229         }
00230         
00231         fdInitDigest(fd, digestalgo, 0);
00232         fsize = 0;
00233         while ((rc = (int) Fread(buf, sizeof(buf[0]), sizeof(buf), fd)) > 0)
00234             fsize += rc;
00235         fdFiniDigest(fd, digestalgo, &dsum, &dlen, asAscii);
00236         if (Ferror(fd))
00237             rc = 1;
00238 
00239         (void) Fclose(fd);
00240         break;
00241     }
00242 
00243     /* Reap the prelink -y helper. */
00244     if (pid) {
00245         int status;
00246 /*@+longunsignedintegral@*/
00247         (void) waitpid(pid, &status, 0);
00248 /*@=longunsignedintegral@*/
00249         if (!WIFEXITED(status) || WEXITSTATUS(status))
00250             rc = 1;
00251     }
00252 
00253 exit:
00254     if (fsizep)
00255         *fsizep = fsize;
00256     if (!rc)
00257         memcpy(digest, dsum, dlen);
00258     dsum = _free(dsum);
00259 
00260     return rc;
00261 }