crypto/dso/dso_dl.c

   1 /*
   2  * Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the OpenSSL license (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 #include "dso_locl.h"
  11
  12 #ifdef DSO_DL
  13
  14 # include <dl.h>
  15
  16 /* Part of the hack in "dl_load" ... */
  17 # define DSO_MAX_TRANSLATED_SIZE 256
  18
  19 static int dl_load(DSO *dso);
  20 static int dl_unload(DSO *dso);
  21 static DSO_FUNC_TYPE dl_bind_func(DSO *dso, const char *symname);
  22 static char *dl_name_converter(DSO *dso, const char *filename);
  23 static char *dl_merger(DSO *dso, const char *filespec1,
  24                        const char *filespec2);
  25 static void *dl_globallookup(const char *name);
  26
  27 static DSO_METHOD dso_meth_dl = {
  28     "OpenSSL 'dl' shared library method",
  29     dl_load,
  30     dl_unload,
  31     dl_bind_func,
  32     NULL,                       /* ctrl */
  33     dl_name_converter,
  34     dl_merger,
  35     NULL,                       /* init */
  36     NULL,                       /* finish */
  37     dl_globallookup
  38 };
  39
  40 DSO_METHOD *DSO_METHOD_openssl(void)
  41 {
  42     return &dso_meth_dl;
  43 }
  44
  45 /*
  46  * For this DSO_METHOD, our meth_data STACK will contain; (i) the handle
  47  * (shl_t) returned from shl_load(). NB: I checked on HPUX11 and shl_t is
  48  * itself a pointer type so the cast is safe.
  49  */
  50
  51 static int dl_load(DSO *dso)
  52 {
  53     shl_t ptr = NULL;
  54     /*
  55      * We don't do any fancy retries or anything, just take the method's (or
  56      * DSO's if it has the callback set) best translation of the
  57      * platform-independent filename and try once with that.
  58      */
  59     char *filename = DSO_convert_filename(dso, NULL);
  60
  61     if (filename == NULL) {
  62         DSOerr(DSO_F_DL_LOAD, DSO_R_NO_FILENAME);
  63         goto err;
  64     }
  65     ptr = shl_load(filename, BIND_IMMEDIATE |
  66                    (dso->flags & DSO_FLAG_NO_NAME_TRANSLATION ? 0 :
  67                     DYNAMIC_PATH), 0L);
  68     if (ptr == NULL) {
  69         DSOerr(DSO_F_DL_LOAD, DSO_R_LOAD_FAILED);
  70         ERR_add_error_data(4, "filename(", filename, "): ", strerror(errno));
  71         goto err;
  72     }
  73     if (!sk_push(dso->meth_data, (char *)ptr)) {
  74         DSOerr(DSO_F_DL_LOAD, DSO_R_STACK_ERROR);
  75         goto err;
  76     }
  77     /*
  78      * Success, stick the converted filename we've loaded under into the DSO
  79      * (it also serves as the indicator that we are currently loaded).
  80      */
  81     dso->loaded_filename = filename;
  82     return (1);
  83  err:
  84     /* Cleanup! */
  85     OPENSSL_free(filename);
  86     if (ptr != NULL)
  87         shl_unload(ptr);
  88     return (0);
  89 }
  90
  91 static int dl_unload(DSO *dso)
  92 {
  93     shl_t ptr;
  94     if (dso == NULL) {
  95         DSOerr(DSO_F_DL_UNLOAD, ERR_R_PASSED_NULL_PARAMETER);
  96         return (0);
  97     }
  98     if (sk_num(dso->meth_data) < 1)
  99         return (1);
 100     /* Is this statement legal? */
 101     ptr = (shl_t) sk_pop(dso->meth_data);
 102     if (ptr == NULL) {
 103         DSOerr(DSO_F_DL_UNLOAD, DSO_R_NULL_HANDLE);
 104         /*
 105          * Should push the value back onto the stack in case of a retry.
 106          */
 107         sk_push(dso->meth_data, (char *)ptr);
 108         return (0);
 109     }
 110     shl_unload(ptr);
 111     return (1);
 112 }
 113
 114 static DSO_FUNC_TYPE dl_bind_func(DSO *dso, const char *symname)
 115 {
 116     shl_t ptr;
 117     void *sym;
 118
 119     if ((dso == NULL) || (symname == NULL)) {
 120         DSOerr(DSO_F_DL_BIND_FUNC, ERR_R_PASSED_NULL_PARAMETER);
 121         return (NULL);
 122     }
 123     if (sk_num(dso->meth_data) < 1) {
 124         DSOerr(DSO_F_DL_BIND_FUNC, DSO_R_STACK_ERROR);
 125         return (NULL);
 126     }
 127     ptr = (shl_t) sk_value(dso->meth_data, sk_num(dso->meth_data) - 1);
 128     if (ptr == NULL) {
 129         DSOerr(DSO_F_DL_BIND_FUNC, DSO_R_NULL_HANDLE);
 130         return (NULL);
 131     }
 132     if (shl_findsym(&ptr, symname, TYPE_UNDEFINED, &sym) < 0) {
 133         DSOerr(DSO_F_DL_BIND_FUNC, DSO_R_SYM_FAILURE);
 134         ERR_add_error_data(4, "symname(", symname, "): ", strerror(errno));
 135         return (NULL);
 136     }
 137     return ((DSO_FUNC_TYPE)sym);
 138 }
 139
 140 static char *dl_merger(DSO *dso, const char *filespec1, const char *filespec2)
 141 {
 142     char *merged;
 143
 144     if (!filespec1 && !filespec2) {
 145         DSOerr(DSO_F_DL_MERGER, ERR_R_PASSED_NULL_PARAMETER);
 146         return (NULL);
 147     }
 148     /*
 149      * If the first file specification is a rooted path, it rules. same goes
 150      * if the second file specification is missing.
 151      */
 152     if (!filespec2 || filespec1[0] == '/') {
 153         merged = OPENSSL_strdup(filespec1);
 154         if (merged == NULL) {
 155             DSOerr(DSO_F_DL_MERGER, ERR_R_MALLOC_FAILURE);
 156             return (NULL);
 157         }
 158     }
 159     /*
 160      * If the first file specification is missing, the second one rules.
 161      */
 162     else if (!filespec1) {
 163         merged = OPENSSL_strdup(filespec2);
 164         if (merged == NULL) {
 165             DSOerr(DSO_F_DL_MERGER, ERR_R_MALLOC_FAILURE);
 166             return (NULL);
 167         }
 168     } else
 169         /*
 170          * This part isn't as trivial as it looks.  It assumes that the
 171          * second file specification really is a directory, and makes no
 172          * checks whatsoever.  Therefore, the result becomes the
 173          * concatenation of filespec2 followed by a slash followed by
 174          * filespec1.
 175          */
 176     {
 177         int spec2len, len;
 178
 179         spec2len = (filespec2 ? strlen(filespec2) : 0);
 180         len = spec2len + (filespec1 ? strlen(filespec1) : 0);
 181
 182         if (spec2len && filespec2[spec2len - 1] == '/') {
 183             spec2len--;
 184             len--;
 185         }
 186         merged = OPENSSL_malloc(len + 2);
 187         if (merged == NULL) {
 188             DSOerr(DSO_F_DL_MERGER, ERR_R_MALLOC_FAILURE);
 189             return (NULL);
 190         }
 191         strcpy(merged, filespec2);
 192         merged[spec2len] = '/';
 193         strcpy(&merged[spec2len + 1], filespec1);
 194     }
 195     return (merged);
 196 }
 197
 198 /*
 199  * This function is identical to the one in dso_dlfcn.c, but as it is highly
 200  * unlikely that both the "dl" *and* "dlfcn" variants are being compiled at
 201  * the same time, there's no great duplicating the code. Figuring out an
 202  * elegant way to share one copy of the code would be more difficult and
 203  * would not leave the implementations independent.
 204  */
 205 static char *dl_name_converter(DSO *dso, const char *filename)
 206 {
 207     char *translated;
 208     int len, rsize, transform;
 209
 210     len = strlen(filename);
 211     rsize = len + 1;
 212     transform = (strstr(filename, "/") == NULL);
 213     {
 214         /* We will convert this to "%s.s?" or "lib%s.s?" */
 215         rsize += strlen(DSO_EXTENSION); /* The length of ".s?" */
 216         if ((DSO_flags(dso) & DSO_FLAG_NAME_TRANSLATION_EXT_ONLY) == 0)
 217             rsize += 3;         /* The length of "lib" */
 218     }
 219     translated = OPENSSL_malloc(rsize);
 220     if (translated == NULL) {
 221         DSOerr(DSO_F_DL_NAME_CONVERTER, DSO_R_NAME_TRANSLATION_FAILED);
 222         return (NULL);
 223     }
 224     if (transform) {
 225         if ((DSO_flags(dso) & DSO_FLAG_NAME_TRANSLATION_EXT_ONLY) == 0)
 226             sprintf(translated, "lib%s%s", filename, DSO_EXTENSION);
 227         else
 228             sprintf(translated, "%s%s", filename, DSO_EXTENSION);
 229     } else
 230         sprintf(translated, "%s", filename);
 231     return (translated);
 232 }
 233
 234 static void *dl_globallookup(const char *name)
 235 {
 236     void *ret;
 237     shl_t h = NULL;
 238
 239     return shl_findsym(&h, name, TYPE_UNDEFINED, &ret) ? NULL : ret;
 240 }
 241 #endif                          /* DSO_DL */