crypto/dso/dso_dl.c

   1 /*
   2  * Copyright 2000-2024 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (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_local.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 int dl_pathbyaddr(void *addr, char *path, int sz);
  26 static void *dl_globallookup(const char *name);
  27
  28 static DSO_METHOD dso_meth_dl = {
  29     "OpenSSL 'dl' shared library method",
  30     dl_load,
  31     dl_unload,
  32     dl_bind_func,
  33     NULL,                       /* ctrl */
  34     dl_name_converter,
  35     dl_merger,
  36     NULL,                       /* init */
  37     NULL,                       /* finish */
  38     dl_pathbyaddr,
  39     dl_globallookup
  40 };
  41
  42 DSO_METHOD *DSO_METHOD_openssl(void)
  43 {
  44     return &dso_meth_dl;
  45 }
  46
  47 /*
  48  * For this DSO_METHOD, our meth_data STACK will contain; (i) the handle
  49  * (shl_t) returned from shl_load(). NB: I checked on HPUX11 and shl_t is
  50  * itself a pointer type so the cast is safe.
  51  */
  52
  53 static int dl_load(DSO *dso)
  54 {
  55     shl_t ptr = NULL;
  56     /*
  57      * We don't do any fancy retries or anything, just take the method's (or
  58      * DSO's if it has the callback set) best translation of the
  59      * platform-independent filename and try once with that.
  60      */
  61     char *filename = DSO_convert_filename(dso, NULL);
  62
  63     if (filename == NULL) {
  64         ERR_raise(ERR_LIB_DSO, DSO_R_NO_FILENAME);
  65         goto err;
  66     }
  67     ptr = shl_load(filename, BIND_IMMEDIATE |
  68                    (dso->flags & DSO_FLAG_NO_NAME_TRANSLATION ? 0 :
  69                     DYNAMIC_PATH), 0L);
  70     if (ptr == NULL) {
  71         char errbuf[160];
  72
  73         if (openssl_strerror_r(errno, errbuf, sizeof(errbuf)))
  74             ERR_raise_data(ERR_LIB_DSO, DSO_R_LOAD_FAILED,
  75                            "filename(%s): %s", filename, errbuf);
  76         else
  77             ERR_raise_data(ERR_LIB_DSO, DSO_R_LOAD_FAILED,
  78                            "filename(%s): errno %d", filename, errno);
  79         goto err;
  80     }
  81     if (!sk_push(dso->meth_data, (char *)ptr)) {
  82         ERR_raise(ERR_LIB_DSO, DSO_R_STACK_ERROR);
  83         goto err;
  84     }
  85     /*
  86      * Success, stick the converted filename we've loaded under into the DSO
  87      * (it also serves as the indicator that we are currently loaded).
  88      */
  89     dso->loaded_filename = filename;
  90     return 1;
  91  err:
  92     /* Cleanup! */
  93     OPENSSL_free(filename);
  94     if (ptr != NULL)
  95         shl_unload(ptr);
  96     return 0;
  97 }
  98
  99 static int dl_unload(DSO *dso)
 100 {
 101     shl_t ptr;
 102     if (dso == NULL) {
 103         ERR_raise(ERR_LIB_DSO, ERR_R_PASSED_NULL_PARAMETER);
 104         return 0;
 105     }
 106     if (sk_num(dso->meth_data) < 1)
 107         return 1;
 108     /* Is this statement legal? */
 109     ptr = (shl_t) sk_pop(dso->meth_data);
 110     if (ptr == NULL) {
 111         ERR_raise(ERR_LIB_DSO, DSO_R_NULL_HANDLE);
 112         /*
 113          * Should push the value back onto the stack in case of a retry.
 114          */
 115         sk_push(dso->meth_data, (char *)ptr);
 116         return 0;
 117     }
 118     shl_unload(ptr);
 119     return 1;
 120 }
 121
 122 static DSO_FUNC_TYPE dl_bind_func(DSO *dso, const char *symname)
 123 {
 124     shl_t ptr;
 125     void *sym;
 126
 127     if ((dso == NULL) || (symname == NULL)) {
 128         ERR_raise(ERR_LIB_DSO, ERR_R_PASSED_NULL_PARAMETER);
 129         return NULL;
 130     }
 131     if (sk_num(dso->meth_data) < 1) {
 132         ERR_raise(ERR_LIB_DSO, DSO_R_STACK_ERROR);
 133         return NULL;
 134     }
 135     ptr = (shl_t) sk_value(dso->meth_data, sk_num(dso->meth_data) - 1);
 136     if (ptr == NULL) {
 137         ERR_raise(ERR_LIB_DSO, DSO_R_NULL_HANDLE);
 138         return NULL;
 139     }
 140     if (shl_findsym(&ptr, symname, TYPE_UNDEFINED, &sym) < 0) {
 141         char errbuf[160];
 142
 143         if (openssl_strerror_r(errno, errbuf, sizeof(errbuf)))
 144             ERR_raise_data(ERR_LIB_DSO, DSO_R_SYM_FAILURE,
 145                            "symname(%s): %s", symname, errbuf);
 146         else
 147             ERR_raise_data(ERR_LIB_DSO, DSO_R_SYM_FAILURE,
 148                            "symname(%s): errno %d", symname, errno);
 149         return NULL;
 150     }
 151     return (DSO_FUNC_TYPE)sym;
 152 }
 153
 154 static char *dl_merger(DSO *dso, const char *filespec1, const char *filespec2)
 155 {
 156     char *merged;
 157
 158     if (!filespec1 && !filespec2) {
 159         ERR_raise(ERR_LIB_DSO, ERR_R_PASSED_NULL_PARAMETER);
 160         return NULL;
 161     }
 162     /*
 163      * If the first file specification is a rooted path, it rules. same goes
 164      * if the second file specification is missing.
 165      */
 166     if (!filespec2 || filespec1[0] == '/') {
 167         merged = OPENSSL_strdup(filespec1);
 168         if (merged == NULL)
 169             return NULL;
 170     }
 171     /*
 172      * If the first file specification is missing, the second one rules.
 173      */
 174     else if (!filespec1) {
 175         merged = OPENSSL_strdup(filespec2);
 176         if (merged == NULL)
 177             return NULL;
 178     } else
 179         /*
 180          * This part isn't as trivial as it looks.  It assumes that the
 181          * second file specification really is a directory, and makes no
 182          * checks whatsoever.  Therefore, the result becomes the
 183          * concatenation of filespec2 followed by a slash followed by
 184          * filespec1.
 185          */
 186     {
 187         int spec2len, len;
 188
 189         spec2len = (filespec2 ? strlen(filespec2) : 0);
 190         len = spec2len + (filespec1 ? strlen(filespec1) : 0);
 191
 192         if (spec2len && filespec2[spec2len - 1] == '/') {
 193             spec2len--;
 194             len--;
 195         }
 196         merged = OPENSSL_malloc(len + 2);
 197         if (merged == NULL)
 198             return NULL;
 199         strcpy(merged, filespec2);
 200         merged[spec2len] = '/';
 201         strcpy(&merged[spec2len + 1], filespec1);
 202     }
 203     return merged;
 204 }
 205
 206 /*
 207  * This function is identical to the one in dso_dlfcn.c, but as it is highly
 208  * unlikely that both the "dl" *and* "dlfcn" variants are being compiled at
 209  * the same time, there's no great duplicating the code. Figuring out an
 210  * elegant way to share one copy of the code would be more difficult and
 211  * would not leave the implementations independent.
 212  */
 213 static char *dl_name_converter(DSO *dso, const char *filename)
 214 {
 215     char *translated;
 216     int len, rsize, transform;
 217
 218     len = strlen(filename);
 219     rsize = len + 1;
 220     transform = (strchr(filename, '/') == NULL);
 221     if (transform) {
 222         /* We will convert this to "%s.s?" or "lib%s.s?" */
 223         rsize += strlen(DSO_EXTENSION); /* The length of ".s?" */
 224         if ((DSO_flags(dso) & DSO_FLAG_NAME_TRANSLATION_EXT_ONLY) == 0)
 225             rsize += 3;         /* The length of "lib" */
 226     }
 227     translated = OPENSSL_malloc(rsize);
 228     if (translated == NULL) {
 229         ERR_raise(ERR_LIB_DSO, DSO_R_NAME_TRANSLATION_FAILED);
 230         return NULL;
 231     }
 232     if (transform) {
 233         if ((DSO_flags(dso) & DSO_FLAG_NAME_TRANSLATION_EXT_ONLY) == 0)
 234             sprintf(translated, "lib%s%s", filename, DSO_EXTENSION);
 235         else
 236             sprintf(translated, "%s%s", filename, DSO_EXTENSION);
 237     } else
 238         sprintf(translated, "%s", filename);
 239     return translated;
 240 }
 241
 242 static int dl_pathbyaddr(void *addr, char *path, int sz)
 243 {
 244     struct shl_descriptor inf;
 245     int i, len;
 246
 247     if (addr == NULL) {
 248         union {
 249             int (*f) (void *, char *, int);
 250             void *p;
 251         } t = {
 252             dl_pathbyaddr
 253         };
 254         addr = t.p;
 255     }
 256
 257     for (i = -1; shl_get_r(i, &inf) == 0; i++) {
 258         if (((size_t)addr >= inf.tstart && (size_t)addr < inf.tend) ||
 259             ((size_t)addr >= inf.dstart && (size_t)addr < inf.dend)) {
 260             len = (int)strlen(inf.filename);
 261             if (sz <= 0)
 262                 return len + 1;
 263             if (len >= sz)
 264                 len = sz - 1;
 265             memcpy(path, inf.filename, len);
 266             path[len++] = 0;
 267             return len;
 268         }
 269     }
 270
 271     return -1;
 272 }
 273
 274 static void *dl_globallookup(const char *name)
 275 {
 276     void *ret;
 277     shl_t h = NULL;
 278
 279     return shl_findsym(&h, name, TYPE_UNDEFINED, &ret) ? NULL : ret;
 280 }
 281 #endif                          /* DSO_DL */