From 7b65c3298f8bb8ff0f5b2a1a8260358039ccad83 Mon Sep 17 00:00:00 2001 From: "Dr. Stephen Henson" Date: Tue, 24 Aug 1999 13:21:35 +0000 Subject: [PATCH] Fix for a bug which meant encrypting BIOs sometimes wouldn't read the final block. --- CHANGES | 7 +++++++ crypto/evp/bio_enc.c | 14 +++++++++++--- 2 files changed, 18 insertions(+), 3 deletions(-) diff --git a/CHANGES b/CHANGES index 5ad39ca2bd..a3a8f2823b 100644 --- a/CHANGES +++ b/CHANGES @@ -4,6 +4,13 @@ Changes between 0.9.4 and 0.9.5 [xx XXX 1999] + *) Fix a horrible bug in enc_read() in crypto/evp/bio_enc.c: if the first data + read consists of only the final block it would not decrypted because + EVP_CipherUpdate() would correctly report zero bytes had been decrypted. + A misplaced 'break' also meant the decrypted final block might not be + copied until the next read. + [Steve Henson] + *) Initial support for DH_METHOD. Again based on RSA_METHOD. Also added a few extra parameters to the DH structure: these will be useful if for example we want the value of 'q' or implement X9.42 DH. diff --git a/crypto/evp/bio_enc.c b/crypto/evp/bio_enc.c index 0a7b1ecf07..36a601897d 100644 --- a/crypto/evp/bio_enc.c +++ b/crypto/evp/bio_enc.c @@ -184,9 +184,11 @@ static int enc_read(BIO *b, char *out, int outl) ctx->ok=i; ctx->buf_off=0; } - else + else + { ret=(ret == 0)?i:ret; - break; + break; + } } else { @@ -194,13 +196,19 @@ static int enc_read(BIO *b, char *out, int outl) (unsigned char *)ctx->buf,&ctx->buf_len, (unsigned char *)&(ctx->buf[8]),i); ctx->cont=1; + /* Note: it is possible for EVP_CipherUpdate to + * decrypt zero bytes because this is or looks like + * the final block: if this happens we should retry + * and either read more data or decrypt the final + * block + */ + if(ctx->buf_len == 0) continue; } if (ctx->buf_len <= outl) i=ctx->buf_len; else i=outl; - if (i <= 0) break; memcpy(out,ctx->buf,i); ret+=i; -- 2.25.1