version 1.10, 2001/09/17 19:27:15 |
version 1.10.2.5, 2002/06/26 18:22:36 |
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#include "key.h" |
#include "key.h" |
#include "ssh-rsa.h" |
#include "ssh-rsa.h" |
#include "compat.h" |
#include "compat.h" |
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#include "ssh.h" |
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/* RSASSA-PKCS1-v1_5 (PKCS #1 v2.0 signature) with SHA1 */ |
/* RSASSA-PKCS1-v1_5 (PKCS #1 v2.0 signature) with SHA1 */ |
int |
int |
ssh_rsa_sign( |
ssh_rsa_sign(Key *key, u_char **sigp, u_int *lenp, |
Key *key, |
u_char *data, u_int datalen) |
u_char **sigp, int *lenp, |
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u_char *data, int datalen) |
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{ |
{ |
const EVP_MD *evp_md; |
const EVP_MD *evp_md; |
EVP_MD_CTX md; |
EVP_MD_CTX md; |
u_char *digest, *sig, *ret; |
u_char digest[EVP_MAX_MD_SIZE], *sig, *ret; |
u_int slen, dlen, len; |
u_int slen, dlen, len; |
int ok, nid; |
int ok, nid; |
Buffer b; |
Buffer b; |
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error("ssh_rsa_sign: EVP_get_digestbynid %d failed", nid); |
error("ssh_rsa_sign: EVP_get_digestbynid %d failed", nid); |
return -1; |
return -1; |
} |
} |
dlen = evp_md->md_size; |
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digest = xmalloc(dlen); |
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EVP_DigestInit(&md, evp_md); |
EVP_DigestInit(&md, evp_md); |
EVP_DigestUpdate(&md, data, datalen); |
EVP_DigestUpdate(&md, data, datalen); |
EVP_DigestFinal(&md, digest, NULL); |
EVP_DigestFinal(&md, digest, &dlen); |
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slen = RSA_size(key->rsa); |
slen = RSA_size(key->rsa); |
sig = xmalloc(slen); |
sig = xmalloc(slen); |
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ok = RSA_sign(nid, digest, dlen, sig, &len, key->rsa); |
ok = RSA_sign(nid, digest, dlen, sig, &len, key->rsa); |
memset(digest, 'd', dlen); |
memset(digest, 'd', sizeof(digest)); |
xfree(digest); |
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if (ok != 1) { |
if (ok != 1) { |
int ecode = ERR_get_error(); |
int ecode = ERR_get_error(); |
error("ssh_rsa_sign: RSA_sign failed: %s", ERR_error_string(ecode, NULL)); |
error("ssh_rsa_sign: RSA_sign failed: %s", |
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ERR_error_string(ecode, NULL)); |
xfree(sig); |
xfree(sig); |
return -1; |
return -1; |
} |
} |
if (len < slen) { |
if (len < slen) { |
int diff = slen - len; |
int diff = slen - len; |
debug("slen %d > len %d", slen, len); |
debug("slen %u > len %u", slen, len); |
memmove(sig + diff, sig, len); |
memmove(sig + diff, sig, len); |
memset(sig, 0, diff); |
memset(sig, 0, diff); |
} else if (len > slen) { |
} else if (len > slen) { |
error("ssh_rsa_sign: slen %d slen2 %d", slen, len); |
error("ssh_rsa_sign: slen %u slen2 %u", slen, len); |
xfree(sig); |
xfree(sig); |
return -1; |
return -1; |
} |
} |
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} |
} |
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int |
int |
ssh_rsa_verify( |
ssh_rsa_verify(Key *key, u_char *signature, u_int signaturelen, |
Key *key, |
u_char *data, u_int datalen) |
u_char *signature, int signaturelen, |
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u_char *data, int datalen) |
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{ |
{ |
Buffer b; |
Buffer b; |
const EVP_MD *evp_md; |
const EVP_MD *evp_md; |
EVP_MD_CTX md; |
EVP_MD_CTX md; |
char *ktype; |
char *ktype; |
u_char *sigblob, *digest; |
u_char digest[EVP_MAX_MD_SIZE], *sigblob; |
u_int len, dlen; |
u_int len, dlen, modlen; |
int rlen, ret, nid; |
int rlen, ret, nid; |
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if (key == NULL || key->type != KEY_RSA || key->rsa == NULL) { |
if (key == NULL || key->type != KEY_RSA || key->rsa == NULL) { |
error("ssh_rsa_verify: no RSA key"); |
error("ssh_rsa_verify: no RSA key"); |
return -1; |
return -1; |
} |
} |
if (BN_num_bits(key->rsa->n) < 768) { |
if (BN_num_bits(key->rsa->n) < SSH_RSA_MINIMUM_MODULUS_SIZE) { |
error("ssh_rsa_verify: n too small: %d bits", |
error("ssh_rsa_verify: RSA modulus too small: %d < minimum %d bits", |
BN_num_bits(key->rsa->n)); |
BN_num_bits(key->rsa->n), SSH_RSA_MINIMUM_MODULUS_SIZE); |
return -1; |
return -1; |
} |
} |
buffer_init(&b); |
buffer_init(&b); |
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sigblob = buffer_get_string(&b, &len); |
sigblob = buffer_get_string(&b, &len); |
rlen = buffer_len(&b); |
rlen = buffer_len(&b); |
buffer_free(&b); |
buffer_free(&b); |
if(rlen != 0) { |
if (rlen != 0) { |
xfree(sigblob); |
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error("ssh_rsa_verify: remaining bytes in signature %d", rlen); |
error("ssh_rsa_verify: remaining bytes in signature %d", rlen); |
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xfree(sigblob); |
return -1; |
return -1; |
} |
} |
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/* RSA_verify expects a signature of RSA_size */ |
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modlen = RSA_size(key->rsa); |
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if (len > modlen) { |
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error("ssh_rsa_verify: len %u > modlen %u", len, modlen); |
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xfree(sigblob); |
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return -1; |
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} else if (len < modlen) { |
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int diff = modlen - len; |
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debug("ssh_rsa_verify: add padding: modlen %u > len %u", |
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modlen, len); |
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sigblob = xrealloc(sigblob, modlen); |
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memmove(sigblob + diff, sigblob, len); |
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memset(sigblob, 0, diff); |
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len = modlen; |
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} |
nid = (datafellows & SSH_BUG_RSASIGMD5) ? NID_md5 : NID_sha1; |
nid = (datafellows & SSH_BUG_RSASIGMD5) ? NID_md5 : NID_sha1; |
if ((evp_md = EVP_get_digestbynid(nid)) == NULL) { |
if ((evp_md = EVP_get_digestbynid(nid)) == NULL) { |
xfree(sigblob); |
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error("ssh_rsa_verify: EVP_get_digestbynid %d failed", nid); |
error("ssh_rsa_verify: EVP_get_digestbynid %d failed", nid); |
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xfree(sigblob); |
return -1; |
return -1; |
} |
} |
dlen = evp_md->md_size; |
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digest = xmalloc(dlen); |
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EVP_DigestInit(&md, evp_md); |
EVP_DigestInit(&md, evp_md); |
EVP_DigestUpdate(&md, data, datalen); |
EVP_DigestUpdate(&md, data, datalen); |
EVP_DigestFinal(&md, digest, NULL); |
EVP_DigestFinal(&md, digest, &dlen); |
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ret = RSA_verify(nid, digest, dlen, sigblob, len, key->rsa); |
ret = RSA_verify(nid, digest, dlen, sigblob, len, key->rsa); |
memset(digest, 'd', dlen); |
memset(digest, 'd', sizeof(digest)); |
xfree(digest); |
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memset(sigblob, 's', len); |
memset(sigblob, 's', len); |
xfree(sigblob); |
xfree(sigblob); |
if (ret == 0) { |
if (ret == 0) { |
int ecode = ERR_get_error(); |
int ecode = ERR_get_error(); |
error("ssh_rsa_verify: RSA_verify failed: %s", ERR_error_string(ecode, NULL)); |
error("ssh_rsa_verify: RSA_verify failed: %s", |
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ERR_error_string(ecode, NULL)); |
} |
} |
debug("ssh_rsa_verify: signature %scorrect", (ret==0) ? "in" : ""); |
debug("ssh_rsa_verify: signature %scorrect", (ret==0) ? "in" : ""); |
return ret; |
return ret; |