Drop support for openssl 0.9.7

097 hasn't seen a new version since 2007; we can drop support too.

This lets us remove our built-in sha256 implementation, and some
checks for old bugs.

5 files changed, 13 insertions, 430 deletions

diff --git a/changes/dropped_openssl_vers b/changes/dropped_openssl_vers
new file mode 100644
index 000000000..dc79d5e3f
--- /dev/null
+++ b/changes/dropped_openssl_vers
@@ -0,0 +1,3 @@
+  o Required libraries:
+    - Tor now requires OpenSSL 0.9.8 or later; OpenSSL 1.0.0 or later is
+      strongly recommended.
diff --git a/src/common/crypto.c b/src/common/crypto.c
index 7768cc37b..6c6bf1489 100644
--- a/src/common/crypto.c
+++ b/src/common/crypto.c
@@ -57,8 +57,8 @@
 #include "container.h"
 #include "compat.h"
 
-#if OPENSSL_VERSION_NUMBER < OPENSSL_V_SERIES(0,9,7)
-#error "We require OpenSSL >= 0.9.7"
+#if OPENSSL_VERSION_NUMBER < OPENSSL_V_SERIES(0,9,8)
+#error "We require OpenSSL >= 0.9.8"
 #endif
 
 #ifdef ANDROID
@@ -69,31 +69,6 @@
 /** Longest recognized */
 #define MAX_DNS_LABEL_SIZE 63
 
-#if OPENSSL_VERSION_NUMBER < OPENSSL_V_SERIES(0,9,8) && \
-  !defined(RUNNING_DOXYGEN)
-/** @{ */
-/** On OpenSSL versions before 0.9.8, there is no working SHA256
- * implementation, so we use Tom St Denis's nice speedy one, slightly adapted
- * to our needs.  These macros make it usable by us. */
-#define SHA256_CTX sha256_state
-#define SHA256_Init sha256_init
-#define SHA256_Update sha256_process
-#define LTC_ARGCHK(x) tor_assert(x)
-/** @} */
-#include "sha256.c"
-#define SHA256_Final(a,b) sha256_done(b,a)
-
-static unsigned char *
-SHA256(const unsigned char *m, size_t len, unsigned char *d)
-{
-  SHA256_CTX ctx;
-  SHA256_Init(&ctx);
-  SHA256_Update(&ctx, m, len);
-  SHA256_Final(d, &ctx);
-  return d;
-}
-#endif
-
 /** Macro: is k a valid RSA public or private key? */
 #define PUBLIC_KEY_OK(k) ((k) && (k)->key && (k)->key->n)
 /** Macro: is k a valid RSA private key? */
@@ -478,11 +453,7 @@ crypto_pk_generate_key_with_bits(crypto_pk_t *env, int bits)
 
   if (env->key)
     RSA_free(env->key);
-#if OPENSSL_VERSION_NUMBER < OPENSSL_V_SERIES(0,9,8)
-  /* In OpenSSL 0.9.7, RSA_generate_key is all we have. */
-  env->key = RSA_generate_key(bits, 65537, NULL, NULL);
-#else
-  /* In OpenSSL 0.9.8, RSA_generate_key is deprecated. */
+
   {
     BIGNUM *e = BN_new();
     RSA *r = NULL;
@@ -503,8 +474,8 @@ crypto_pk_generate_key_with_bits(crypto_pk_t *env, int bits)
       BN_free(e);
     if (r)
       RSA_free(r);
-    }
-#endif
+  }
+
   if (!env->key) {
     crypto_log_errors(LOG_WARN, "generating RSA key");
     return -1;
@@ -1660,63 +1631,11 @@ crypto_hmac_sha256(char *hmac_out,
                    const char *key, size_t key_len,
                    const char *msg, size_t msg_len)
 {
-#if OPENSSL_VERSION_NUMBER >= OPENSSL_V_SERIES(0,9,8)
   /* If we've got OpenSSL >=0.9.8 we can use its hmac implementation. */
   tor_assert(key_len < INT_MAX);
   tor_assert(msg_len < INT_MAX);
   HMAC(EVP_sha256(), key, (int)key_len, (unsigned char*)msg, (int)msg_len,
        (unsigned char*)hmac_out, NULL);
-#else
-  /* OpenSSL doesn't have an EVP implementation for SHA256. We'll need
-     to do HMAC on our own.
-
-     HMAC isn't so hard: To compute HMAC(key, msg):
-      1. If len(key) > blocksize, key = H(key).
-      2. If len(key) < blocksize, right-pad key up to blocksize with 0 bytes.
-      3. let ipad = key xor 0x363636363636....36
-         let opad = key xor 0x5c5c5c5c5c5c....5c
-         The result is H(opad | H( ipad | msg ) )
-  */
-#define BLOCKSIZE 64
-#define DIGESTSIZE 32
-  uint8_t k[BLOCKSIZE];
-  uint8_t pad[BLOCKSIZE];
-  uint8_t d[DIGESTSIZE];
-  int i;
-  SHA256_CTX st;
-
-  tor_assert(key_len < INT_MAX);
-  tor_assert(msg_len < INT_MAX);
-
-  if (key_len <= BLOCKSIZE) {
-    memset(k, 0, sizeof(k));
-    memcpy(k, key, key_len); /* not time invariant in key_len */
-  } else {
-    SHA256((const uint8_t *)key, key_len, k);
-    memset(k+DIGESTSIZE, 0, sizeof(k)-DIGESTSIZE);
-  }
-  for (i = 0; i < BLOCKSIZE; ++i)
-    pad[i] = k[i] ^ 0x36;
-  SHA256_Init(&st);
-  SHA256_Update(&st, pad, BLOCKSIZE);
-  SHA256_Update(&st, (uint8_t*)msg, msg_len);
-  SHA256_Final(d, &st);
-
-  for (i = 0; i < BLOCKSIZE; ++i)
-    pad[i] = k[i] ^ 0x5c;
-  SHA256_Init(&st);
-  SHA256_Update(&st, pad, BLOCKSIZE);
-  SHA256_Update(&st, d, DIGESTSIZE);
-  SHA256_Final((uint8_t*)hmac_out, &st);
-
-  /* Now clear everything. */
-  memset(k, 0, sizeof(k));
-  memset(pad, 0, sizeof(pad));
-  memset(d, 0, sizeof(d));
-  memset(&st, 0, sizeof(st));
-#undef BLOCKSIZE
-#undef DIGESTSIZE
-#endif
 }
 
 /* DH */
@@ -2319,9 +2238,7 @@ crypto_dh_free(crypto_dh_t *dh)
  * that fd without checking whether it fit in the fd_set.  Thus, if the
  * system has not just been started up, it is unsafe to call */
 #define RAND_POLL_IS_SAFE                       \
-  ((OPENSSL_VERSION_NUMBER >= OPENSSL_V(0,9,7,'j') &&        \
-    OPENSSL_VERSION_NUMBER < OPENSSL_V_SERIES(0,9,8)) ||     \
-   OPENSSL_VERSION_NUMBER >= OPENSSL_V(0,9,8,'c'))
+  (OPENSSL_VERSION_NUMBER >= OPENSSL_V(0,9,8,'c'))
 
 /** Set the seed of the weak RNG to a random value. */
 static void
diff --git a/src/common/include.am b/src/common/include.am
index 299c92e06..ba08aa7e5 100644
--- a/src/common/include.am
+++ b/src/common/include.am
@@ -3,7 +3,6 @@ noinst_LIBRARIES+= src/common/libor.a src/common/libor-crypto.a src/common/libor
 
 EXTRA_DIST+= \
   src/common/common_sha1.i	\
-  src/common/sha256.c		\
   src/common/Makefile.nmake
 
 #CFLAGS  = -Wall -Wpointer-arith -O2
@@ -72,4 +71,4 @@ src/common/common_sha1.i: $(libor_SOURCES) $(libor_crypto_a_SOURCES) $(COMMONHEA
 	fi
 
 src/common/util_codedigest.o: src/common/common_sha1.i
-src/common/crypto.o: src/common/sha256.c
+
diff --git a/src/common/sha256.c b/src/common/sha256.c
deleted file mode 100644
index 813c68d2a..000000000
--- a/src/common/sha256.c
+++ /dev/null
@@ -1,331 +0,0 @@
-/* Copyright (c) 2009-2012, The Tor Project, Inc. */
-/* See LICENSE for licensing information */
-/* This SHA256 implementation is adapted from the public domain one in
-   LibTomCrypt, version 1.6.  Tor uses it on platforms where OpenSSL doesn't
-   have a SHA256. */
-
-
-typedef struct sha256_state {
-    uint64_t length;
-    uint32_t state[8], curlen;
-    unsigned char buf[64];
-} sha256_state;
-
-#define CRYPT_OK 0
-#define CRYPT_NOP -1
-#define CRYPT_INVALID_ARG -2
-
-#define LOAD32H(x,y) STMT_BEGIN x = ntohl(get_uint32((const char*)y)); STMT_END
-#define STORE32H(x,y) STMT_BEGIN set_uint32((char*)y, htonl(x)); STMT_END
-#define STORE64H(x,y) STMT_BEGIN                                \
-  set_uint32((char*)y, htonl((uint32_t)((x)>>32)));             \
-  set_uint32(((char*)y)+4, htonl((uint32_t)((x)&0xffffffff)));  \
-  STMT_END
-#define RORc(x, y) ( ((((unsigned long)(x)&0xFFFFFFFFUL)>>(unsigned long)((y)&31)) | ((unsigned long)(x)<<(unsigned long)(32-((y)&31)))) & 0xFFFFFFFFUL)
-#ifndef MIN
-   #define MIN(x, y) ( ((x)<(y))?(x):(y) )
-#endif
-
-
-/* LibTomCrypt, modular cryptographic library -- Tom St Denis
- *
- * LibTomCrypt is a library that provides various cryptographic
- * algorithms in a highly modular and flexible manner.
- *
- * The library is free for all purposes without any express
- * guarantee it works.
- *
- * Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.com
- */
-
-/**
-  @file sha256.c
-  SHA256 by Tom St Denis
-*/
-
-
-#ifdef LTC_SMALL_CODE
-/* the K array */
-static const uint32_t K[64] = {
-    0x428a2f98UL, 0x71374491UL, 0xb5c0fbcfUL, 0xe9b5dba5UL, 0x3956c25bUL,
-    0x59f111f1UL, 0x923f82a4UL, 0xab1c5ed5UL, 0xd807aa98UL, 0x12835b01UL,
-    0x243185beUL, 0x550c7dc3UL, 0x72be5d74UL, 0x80deb1feUL, 0x9bdc06a7UL,
-    0xc19bf174UL, 0xe49b69c1UL, 0xefbe4786UL, 0x0fc19dc6UL, 0x240ca1ccUL,
-    0x2de92c6fUL, 0x4a7484aaUL, 0x5cb0a9dcUL, 0x76f988daUL, 0x983e5152UL,
-    0xa831c66dUL, 0xb00327c8UL, 0xbf597fc7UL, 0xc6e00bf3UL, 0xd5a79147UL,
-    0x06ca6351UL, 0x14292967UL, 0x27b70a85UL, 0x2e1b2138UL, 0x4d2c6dfcUL,
-    0x53380d13UL, 0x650a7354UL, 0x766a0abbUL, 0x81c2c92eUL, 0x92722c85UL,
-    0xa2bfe8a1UL, 0xa81a664bUL, 0xc24b8b70UL, 0xc76c51a3UL, 0xd192e819UL,
-    0xd6990624UL, 0xf40e3585UL, 0x106aa070UL, 0x19a4c116UL, 0x1e376c08UL,
-    0x2748774cUL, 0x34b0bcb5UL, 0x391c0cb3UL, 0x4ed8aa4aUL, 0x5b9cca4fUL,
-    0x682e6ff3UL, 0x748f82eeUL, 0x78a5636fUL, 0x84c87814UL, 0x8cc70208UL,
-    0x90befffaUL, 0xa4506cebUL, 0xbef9a3f7UL, 0xc67178f2UL
-};
-#endif
-
-/* Various logical functions */
-#define Ch(x,y,z)       (z ^ (x & (y ^ z)))
-#define Maj(x,y,z)      (((x | y) & z) | (x & y))
-#define S(x, n)         RORc((x),(n))
-#define R(x, n)         (((x)&0xFFFFFFFFUL)>>(n))
-#define Sigma0(x)       (S(x, 2) ^ S(x, 13) ^ S(x, 22))
-#define Sigma1(x)       (S(x, 6) ^ S(x, 11) ^ S(x, 25))
-#define Gamma0(x)       (S(x, 7) ^ S(x, 18) ^ R(x, 3))
-#define Gamma1(x)       (S(x, 17) ^ S(x, 19) ^ R(x, 10))
-
-/* compress 512-bits */
-#ifdef LTC_CLEAN_STACK
-static int _sha256_compress(sha256_state * md, unsigned char *buf)
-#else
-static int  sha256_compress(sha256_state * md, unsigned char *buf)
-#endif
-{
-    uint32_t S[8], W[64], t0, t1;
-#ifdef LTC_SMALL_CODE
-    uint32_t t;
-#endif
-    int i;
-
-    /* copy state into S */
-    for (i = 0; i < 8; i++) {
-        S[i] = md->state[i];
-    }
-
-    /* copy the state into 512-bits into W[0..15] */
-    for (i = 0; i < 16; i++) {
-        LOAD32H(W[i], buf + (4*i));
-    }
-
-    /* fill W[16..63] */
-    for (i = 16; i < 64; i++) {
-        W[i] = Gamma1(W[i - 2]) + W[i - 7] + Gamma0(W[i - 15]) + W[i - 16];
-    }
-
-    /* Compress */
-#ifdef LTC_SMALL_CODE
-#define RND(a,b,c,d,e,f,g,h,i)                         \
-     t0 = h + Sigma1(e) + Ch(e, f, g) + K[i] + W[i];   \
-     t1 = Sigma0(a) + Maj(a, b, c);                    \
-     d += t0;                                          \
-     h  = t0 + t1;
-
-     for (i = 0; i < 64; ++i) {
-         RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],i);
-         t = S[7]; S[7] = S[6]; S[6] = S[5]; S[5] = S[4];
-         S[4] = S[3]; S[3] = S[2]; S[2] = S[1]; S[1] = S[0]; S[0] = t;
-     }
-#else
-#define RND(a,b,c,d,e,f,g,h,i,ki)                    \
-     t0 = h + Sigma1(e) + Ch(e, f, g) + ki + W[i];   \
-     t1 = Sigma0(a) + Maj(a, b, c);                  \
-     d += t0;                                        \
-     h  = t0 + t1;
-
-    RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],0,0x428a2f98);
-    RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],1,0x71374491);
-    RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],2,0xb5c0fbcf);
-    RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],3,0xe9b5dba5);
-    RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],4,0x3956c25b);
-    RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],5,0x59f111f1);
-    RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],6,0x923f82a4);
-    RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],7,0xab1c5ed5);
-    RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],8,0xd807aa98);
-    RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],9,0x12835b01);
-    RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],10,0x243185be);
-    RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],11,0x550c7dc3);
-    RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],12,0x72be5d74);
-    RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],13,0x80deb1fe);
-    RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],14,0x9bdc06a7);
-    RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],15,0xc19bf174);
-    RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],16,0xe49b69c1);
-    RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],17,0xefbe4786);
-    RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],18,0x0fc19dc6);
-    RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],19,0x240ca1cc);
-    RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],20,0x2de92c6f);
-    RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],21,0x4a7484aa);
-    RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],22,0x5cb0a9dc);
-    RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],23,0x76f988da);
-    RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],24,0x983e5152);
-    RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],25,0xa831c66d);
-    RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],26,0xb00327c8);
-    RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],27,0xbf597fc7);
-    RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],28,0xc6e00bf3);
-    RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],29,0xd5a79147);
-    RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],30,0x06ca6351);
-    RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],31,0x14292967);
-    RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],32,0x27b70a85);
-    RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],33,0x2e1b2138);
-    RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],34,0x4d2c6dfc);
-    RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],35,0x53380d13);
-    RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],36,0x650a7354);
-    RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],37,0x766a0abb);
-    RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],38,0x81c2c92e);
-    RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],39,0x92722c85);
-    RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],40,0xa2bfe8a1);
-    RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],41,0xa81a664b);
-    RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],42,0xc24b8b70);
-    RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],43,0xc76c51a3);
-    RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],44,0xd192e819);
-    RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],45,0xd6990624);
-    RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],46,0xf40e3585);
-    RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],47,0x106aa070);
-    RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],48,0x19a4c116);
-    RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],49,0x1e376c08);
-    RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],50,0x2748774c);
-    RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],51,0x34b0bcb5);
-    RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],52,0x391c0cb3);
-    RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],53,0x4ed8aa4a);
-    RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],54,0x5b9cca4f);
-    RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],55,0x682e6ff3);
-    RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],56,0x748f82ee);
-    RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],57,0x78a5636f);
-    RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],58,0x84c87814);
-    RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],59,0x8cc70208);
-    RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],60,0x90befffa);
-    RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],61,0xa4506ceb);
-    RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],62,0xbef9a3f7);
-    RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],63,0xc67178f2);
-
-#undef RND
-
-#endif
-
-    /* feedback */
-    for (i = 0; i < 8; i++) {
-        md->state[i] = md->state[i] + S[i];
-    }
-    return CRYPT_OK;
-}
-
-#ifdef LTC_CLEAN_STACK
-static int sha256_compress(sha256_state * md, unsigned char *buf)
-{
-    int err;
-    err = _sha256_compress(md, buf);
-    burn_stack(sizeof(uint32_t) * 74);
-    return err;
-}
-#endif
-
-/**
-   Initialize the hash state
-   @param md   The hash state you wish to initialize
-   @return CRYPT_OK if successful
-*/
-static int sha256_init(sha256_state * md)
-{
-    LTC_ARGCHK(md != NULL);
-
-    md->curlen = 0;
-    md->length = 0;
-    md->state[0] = 0x6A09E667UL;
-    md->state[1] = 0xBB67AE85UL;
-    md->state[2] = 0x3C6EF372UL;
-    md->state[3] = 0xA54FF53AUL;
-    md->state[4] = 0x510E527FUL;
-    md->state[5] = 0x9B05688CUL;
-    md->state[6] = 0x1F83D9ABUL;
-    md->state[7] = 0x5BE0CD19UL;
-    return CRYPT_OK;
-}
-
-/**
-   Process a block of memory though the hash
-   @param md     The hash state
-   @param in     The data to hash
-   @param inlen  The length of the data (octets)
-   @return CRYPT_OK if successful
-*/
-static int sha256_process (sha256_state * md, const unsigned char *in, unsigned long inlen)
-{
-    unsigned long n;
-    int           err;
-    LTC_ARGCHK(md != NULL);
-    LTC_ARGCHK(in != NULL);
-    if (md->curlen > sizeof(md->buf)) {
-       return CRYPT_INVALID_ARG;
-    }
-    while (inlen > 0) {
-        if (md->curlen == 0 && inlen >= 64) {
-           if ((err = sha256_compress (md, (unsigned char *)in)) != CRYPT_OK) {
-              return err;
-           }
-           md->length += 64 * 8;
-           in             += 64;
-           inlen          -= 64;
-        } else {
-           n = MIN(inlen, (64 - md->curlen));
-           memcpy(md->buf + md->curlen, in, (size_t)n);
-           md->curlen += n;
-           in             += n;
-           inlen          -= n;
-           if (md->curlen == 64) {
-              if ((err = sha256_compress (md, md->buf)) != CRYPT_OK) {
-                 return err;
-              }
-              md->length += 8*64;
-              md->curlen = 0;
-           }
-       }
-    }
-    return CRYPT_OK;
-}
-
-/**
-   Terminate the hash to get the digest
-   @param md  The hash state
-   @param out [out] The destination of the hash (32 bytes)
-   @return CRYPT_OK if successful
-*/
-static int sha256_done(sha256_state * md, unsigned char *out)
-{
-    int i;
-
-    LTC_ARGCHK(md  != NULL);
-    LTC_ARGCHK(out != NULL);
-
-    if (md->curlen >= sizeof(md->buf)) {
-       return CRYPT_INVALID_ARG;
-    }
-
-
-    /* increase the length of the message */
-    md->length += md->curlen * 8;
-
-    /* append the '1' bit */
-    md->buf[md->curlen++] = (unsigned char)0x80;
-
-    /* if the length is currently above 56 bytes we append zeros
-     * then compress.  Then we can fall back to padding zeros and length
-     * encoding like normal.
-     */
-    if (md->curlen > 56) {
-        while (md->curlen < 64) {
-            md->buf[md->curlen++] = (unsigned char)0;
-        }
-        sha256_compress(md, md->buf);
-        md->curlen = 0;
-    }
-
-    /* pad upto 56 bytes of zeroes */
-    while (md->curlen < 56) {
-        md->buf[md->curlen++] = (unsigned char)0;
-    }
-
-    /* store length */
-    STORE64H(md->length, md->buf+56);
-    sha256_compress(md, md->buf);
-
-    /* copy output */
-    for (i = 0; i < 8; i++) {
-        STORE32H(md->state[i], out+(4*i));
-    }
-#ifdef LTC_CLEAN_STACK
-    zeromem(md, sizeof(sha256_state));
-#endif
-    return CRYPT_OK;
-}
-
-/* $Source: /cvs/libtom/libtomcrypt/src/hashes/sha2/sha256.c,v $ */
-/* $Revision: 1.9 $ */
-/* $Date: 2006/11/01 09:28:17 $ */
diff --git a/src/common/tortls.c b/src/common/tortls.c
index a3485c768..841156db2 100644
--- a/src/common/tortls.c
+++ b/src/common/tortls.c
@@ -58,8 +58,8 @@
 #include "container.h"
 #include <string.h>
 
-#if OPENSSL_VERSION_NUMBER < OPENSSL_V_SERIES(0,9,7)
-#error "We require OpenSSL >= 0.9.7"
+#if OPENSSL_VERSION_NUMBER < OPENSSL_V_SERIES(0,9,8)
+#error "We require OpenSSL >= 0.9.8"
 #endif
 
 /* Enable the "v2" TLS handshake.
@@ -778,13 +778,8 @@ tor_cert_decode(const uint8_t *certificate, size_t certificate_len)
   if (certificate_len > INT_MAX)
     return NULL;
 
-#if OPENSSL_VERSION_NUMBER < OPENSSL_V_SERIES(0,9,8)
-  /* This ifdef suppresses a type warning.  Take out this case once everybody
-   * is using OpenSSL 0.9.8 or later. */
-  x509 = d2i_X509(NULL, (unsigned char**)&cp, (int)certificate_len);
-#else
   x509 = d2i_X509(NULL, &cp, (int)certificate_len);
-#endif
+
   if (!x509)
     return NULL; /* Couldn't decode */
   if (cp - certificate != (int)certificate_len) {